bluuebunny/crossref_metadata_2025 huggingface dataset:
Bioequivalence and Narrow Therapeutic Index Drugs
Authors: Benet Leslie Z. , Goyan Jere E.
Published: October 2023

Every prescription written for a generic drug requires an act of faith by the prescriber that any one of the several available products will be therapeutically equivalent to the innovator (brand name) products. Concerns about this act of faith have been expressed for many years, particularly in the wake of the generic scandals that occurred in 1989–1990, and especially relative to the drugs with a narrow therapeutic range. We contend that these drugs are actually the least likely to pose problems in ensuring therapeutic equivalence, but that new criteria must be established for bioequivalence because the present system is wasteful and is stifling innovation in the industry. We propose four suggestions to the scientific and regulatory communities that we believe could assist in modifying the process such that innovation is encouraged and practitioners are reassured relative to the appropriateness of using generic drugs.
Pharmacokinetics and Pharmacodynamics of Glipizide After Once‐Daily and Divided Doses
Authors: Kradjan Wayne A. , Takeuchi Kathy Y. , Opheim Kent E. , Wood Francis C.
Published: October 2023

Study Objective. To determine the pharmacokinetics and pharmacodynamics of glipizide given as a single, oral, 20‐mg dose, versus three different divided‐dose regimens totaling 20 mg each.

Design. Randomized (in order of dosing regimens), open‐label, crossover study.

Setting. University medical center clinical research center.

Patients. Six subjects with noninsulin‐dependent diabetes mellitus.

Interventions. Patients were studied on four separate occasions separated by at least 3 days. The divided‐dose regimens were designed to simulate delayed absorption of the drug over 2, 4, and 8 hours. Blood samples for measuring glipizide, glucose, and C‐peptide were obtained over 24 hours.

Measurements and Main Results. Glipizide peak concentrations and time to peak differed significantly with the dosage schedule; when smaller doses were administered more often, peak concentrations were lower and more delayed. The mean values for area under the curve from time zero to infinity (range 7240.7–10,001.8 μg·L‐1·hr−1; 16,226‐22,414 nmol·L−1·hr−1), clearance (0.44‐0.64 ml·min−1·kg−1; 0.07‐0.11 ml·sec−1·kg−1), post‐distribution phase volume (0.17‐0.25 L·kg−1), and half‐life (4.2–5.4 hrs) were not significantly different among regimens. Neither morning fasting glucose nor maximum and minimum times and concentrations of glucose and C‐peptide over 24 hours were statistically different among regimens. Similarly, no significant differences were found in area under the concentration‐time curve for glucose and C‐peptide measured over 2.5 hours after each meal and from time zero to 24 hours.

Conclusions. The timing of a glipizide dose in relation to a meal and simulated delayed or prolonged absorption appear to have little influence on the drug's pharmacodynamic effects.
Piperacillin‐Tazobactam Pharmacokinetics in Patients With Intraabdominal Infections
Authors: Jhee Stanford S. , Kern Jack W. , Burm Jin‐Pil , Yellin Albert E. , Gill Mark A.
Published: October 2023

Study Objective. To determine the appropriate compartmental and noncompartmental pharmacokinetic parameters for intravenous piperacillin and tazobactam.

Design. Sequential selection of patients entered into a randomized, open‐label clinical efficacy trial.

Setting. Los Angeles County‐University of Southern California Medical Center.

Participants. Sequential sample of 18 patients admitted for intraabdominal infections and consented into a comparative antibiotic trial.

Interventions. Patients received piperacillin 4 g plus tazobactam 500 mg by intravenous intermittent infusion every 8 hours.

Measurements and Main Results. The estimated noncompartmental pharmacokinetic parameters (mean ± SD) for piperacillin and tazobactam, respectively, were as follows: maximum concentration in plasma 218.7 ± 48.9 μg/ml and 27.8 ± 9.1 μg/ml; half‐life 1.07 ± 0.22 hours and 1.00 ± 0.27 hours; elimination rate constant 0.67 ± 0.13 hr−1 and 0.73 ± 0.18 hr−1; area under the concentration‐time curve from zero hour to infinity 288.5 ± 71.25 mg·hr/L and 36.3 ± 9.55 mg·hr/L; total plasma clearance 14.75 ± 3.93 L/hour and 14.78 ± 4.39 L/hour; renal clearance 5.69 ± 1.94 L/hour and 7.85 ± 3.37 L/hour; volume of distribution at steady state 21.00 ± 4.18 L and 22.47 ± 8.27 L; and mean residence time 1.72 ± 0.29 hours and 1.79 ± 0.35 hours.

Conclusion. Our findings were similar to those in other surgical patient models. The two‐compartmental model best described piperacillin and tazobactam disposition in our patients. Bayesian analyses of the two‐compartment models of piperacillin and tazobactam were able to predict trough, peak, and 2‐hour postadministration levels without bias.
The Effect of Age and Everyday Exercise on Steady‐State Plasma Digoxin Concentrations
Authors: Teague A. Christine , Garnett William R. , Briggs Geneva C. , Stanley Holly R.
Published: October 2023

Age‐related physiologic changes may significantly alter the disposition and pharmacologic characteristics of many drugs. The elderly are the most frequent users of digoxin because of increased prevalence of atrial fibrillation and congestive heart failure. This study was conducted to confirm the decrease in digoxin concentrations during exercise, to determine if age is a factor in this decrease, and to explore the difference between chronologic age and physiologic age. Eighteen men age 50–85 years were treated with digoxin for more than 1 month before enrolling and had serum digoxin concentrations of 0.4‐2.0 μg/L. They were evaluated during a 3‐hour period in the morning (A.M. dose withheld). Blood samples were obtained every 10 minutes during sequential 60‐minute periods of rest (phase I), walking (phase II), and rest (phase III). There were no significant differences in mean concentration between phases II and I (p<0.76), phases III and phase I (p<0.70), or phases II and III (p<0.37). The effect of age was positively correlated with the mean concentration of phase II but was not statistically significant (p<0.62). Statistically significant correlations were seen only between the exercise phase and serum albumin and Mini‐Mental Status Examination scores. We conclude that exercise has minimal, if any, clinically relevant effects on plasma digoxin concentrations. Increasing chronologic age has no influence on a decrease in the concentrations with exercise; a younger physiologic age may play a role.
Atracurium Resistance in a Critically Ill Patient
Authors: Tschida Suzanne J. , Hoey Lori L. , Nahum Avi , Vance‐Bryan Kyle
Published: October 2023

A previously healthy 25‐year‐old man with metastatic testicular teratocarcinoma became resistant to atracurium‐induced neuromuscular blockade as evidenced by train‐of‐four (TOF) monitoring combined with clinical assessment. Subsequently he had an adequate response with a standard dosage of pancuronium. During the first 10 days of neuromuscular blockade, the atracurium requirements escalated from 0.31 to 1.7 mg/kg/hour, guided by TOF monitoring, movement, and spontaneous respirations. The infusion was discontinued but later reinstituted. Despite a total atracurium loading dose of 1.4 mg/kg followed by an infusion rate titrated to 1.7 mg/kg/hour, inadequate paralysis persisted. Atracurium was terminated and an intravenous infusion of pancuronium 0.10 mg/kg/hour was started. Over the next 3 days the pancuronium infusion was titrated down to a range of 0.04‐0.06 mg/kg/hour, followed by a maintenance infusion of 0.01‐0.05 mg/kg/hour for 5 days. A pharmacokinetic alteration, such as increased metabolism or elimination, may have caused the atracurium resistance.
Amnesia Possibly Associated with Zolpidem Administration
Authors: Canaday Bruce R.
Published: October 2023

Two patients experienced amnesia after taking Zolpidem 5 and 10 mg. Neither patient could recall telephone conversations that took place within an hour of taking the drug. The first patient placed a call shortly after ingestion; the second took the dose, fell asleep, and was awakened by the call. Health care providers should be aware of the possibility that in some patients, sedative‐hypnotic agents such as Zolpidem may produce amnesia that begins a short time after ingestion and may persist into the sleep cycle. This may be particularly important in individuals who, after taking a hypnotic agent, may have to make significant decisions that they must be able to remember.
Evaluation and Prognostication of Gd‐EOB‐DTPA MRI and CT in Patients With Macrotrabecular‐Massive Hepatocellular Carcinoma
Authors: Cheng Jie , Li Xiaofeng , Wang Limei , Chen Fengxi , Li Yiman , Zuo Guojiao , Pei Mi , Zhang Huarong , Yu Linze , Liu Chen , Wang Jian , Han Qi , Cai Ping , Li Xiaoming
Published: October 2023

Background

Macrotrabecular‐massive hepatocellular carcinoma (MTM‐HCC) is highly aggressive. Comparing the diagnosis ability of CT and gadoxetate disodium (Gd‐EOB‐DTPA) MRI for MTM‐HCC are lacking.

Purpose

To compare the performance of Gd‐EOB‐DTPA MRI and CT for differentiating MTM‐HCC from non‐MTM‐HCC, and determine the prognostic indicator.

Study Type

Retrospective.

Subjects

Post‐surgery HCC patients, divided into the training (N = 272) and external validation (N = 44) cohorts.

Field Strength/Sequence

3.0 T, T1‐weighted imaging, in‐opp phase, and T1‐weighted volumetric interpolated breath‐hold examination/liver acquisition with volume acceleration; enhanced CT.

Assessment

Three radiologists evaluated clinical characteristics (sex, age, liver disease, liver function, blood routine, alpha‐fetoprotein [AFP] and prothrombin time international normalization ratio [PT‐INR]) and imaging features (tumor length, intratumor fat, hemorrhage, arterial phase peritumoral enhancement, intratumor necrosis or ischemia, capsule, and peritumoral hepatobiliary phase [HBP] hypointensity). Compared the performance of CT and MRI for diagnosing MTM‐HCC. Follow‐up occurred every 3–6 months, and nomogram demonstrated the probability of MTM‐HCC.

Statistical Tests

Fisher test, t‐test or Wilcoxon rank‐sum test, area under the curve (AUC), 95% confidence interval (CI), multivariable logistic regression, Kaplan–Meier curve, and Cox proportional hazards. Significance level: P < 0.05.

Results

Gd‐EOB‐DTPA MRI (AUC: 0.793; 95% CI, 0.740–0.839) outperformed CT (AUC: 0.747; 95% CI, 0.691–0.797) in the training cohort. The nomogram, incorporating AFP, PT‐INR, and MRI features (non‐intratumor fat, incomplete capsule, intratumor necrosis or ischemia, and peritumoral HBP hypointensity) demonstrated powerful performance for diagnosing MTM‐HCC with an AUC of 0.826 (95% CI, 0.631–1.000) in the external validation cohort. Median follow‐up was 347 days (interquartile range [IQR], 606 days) for the training cohort and 222 days (IQR, 441 days) for external validation cohort. Intratumor necrosis or ischemia was an independent indicator for poor prognosis.

Data Conclusion

Gd‐EOB‐DTPA MRI might assist in preoperative diagnosis of MTM‐HCC, and intratumor necrosis or ischemia was associated with poor prognosis.

Evidence Level

4

Technical Efficacy

Stage 2
Effect of long‐term strip tillage on soil macropore structure in cool black soil region of Northeast China
Authors: Han Jinze , Li Jianye , Jiang Yanyan , Wang Dichen , Chen Qiang , Zhang Xingyi
Published: October 2023

Soil pore structure is essential for storing and transporting water, and it can be affected by different tillage practices. Strip tillage (ST) is an innovative technology aimed at addressing the challenge of reduced crop yield caused by no‐tillage (NT) in the cool black soil region of Northeast China. Nevertheless, what remains unclear is the influence of ST on soil pore structure in the cool black soil region. After conducting a 14‐year long‐term positioning experiment, this study investigated the variations in spatial distribution patterns of soil macropores under ST practice using X‐ray computed microtomography (μCT). The research also examined, the response of soil organic carbon (SOC) and soil bulk density to ST compared to conventional tillage (CT). This finding revealed that ST significantly increased the macroporosity (>25 μm) at 0–20 cm depths in comparison with CT. The detailed analysis of soil pore size distribution revealed a significant increase in macroporosity of the >2000 μm pore sizes in 0–10 cm layer by 144.79% because of ST. Furthermore, ST significantly increased pore connectivity at the 0–10 cm depth by 3.37% and pore fractal dimension at the 10–20 cm depth by 13.42%. Meanwhile, there was a significant correlation among the changes in soil bulk density, SOC content, macroporosity, pore connectivity, and pore tortuosity, indicating soil bulk density and SOC have a substantial impact on the pore structure. Overall, the implementation of ST leads to a significant enhancement in soil pore structure, improving the understanding of the regulatory mechanism of ST in the cool black soil region of Northeast China. This research aids in advancing the conservation and sustainable utilization of black soil.
Photochromic 3D Optical Storage: Laser‐Induced Regulation of Localized Optical Basicity of Glass
Authors: Li Xuefeng , Wu Yaman , Lin Hang , Chen Gengxu , Hao Yanxue , Wang Pengfei , Lin Shisheng , Xu Ju , Cheng Yao , Wang Yuansheng
Published: October 2023

3D optical storage, spatially expanding storage capacity, is regarded as an effective and economical way to break the diffraction limit of the conventional 2D optical storage. In this study, a new kind of 3D optical storage medium, i.e., vanadium ions (V5+) doped sodium borate glass, is developed, showing intriguing spatially‐selected photochromism (PC) upon laser driven excitation. Significantly, a brand‐new PC mechanism of V5+‐aggregation regulated by localized optical basicity (OB) of glass is proposed and demonstrated. The developed PC glass is responsive to a low‐price desktop‐level mini‐laser to encode optical information, yields unique twofold decoding modes in bright‐ and dark‐fields, and shows good data erasibility. 3D volumetric optical storage with a memory density of ≈480 Mbit cm−3 is realized with the aid of an advanced femtosecond laser micro‐machining system. The findings suggest a novel design approach to fabricate 3D PC glass in terms of manipulating the scale of optical basicity in glass, hopefully stimulating the development of new multi‐dimensional PC optical storage media.
Zn2+/Poly(2‐Hydroxyethyl Acrylate/Itaconic Acid) Hydrogels as Potential Antibacterial Wound Dressings
Authors: Vuković Jovana S. , Radić1 Marija M. Babić , Trifunović Saša B. , Koch Thomas , Perić‐Grujić Aleksandra A. , Vojnović Sandra , Tomić Simonida Lj.
Published: October 2023

Antibacterial hydrogels, as an advanced approach, can create optimal conditions for wound healing, even in the fight against stubborn and difficult‐to‐treat wound infections. Interestingly, pH is an often neglected clinical parameter, although it has a significant impact on the wound healing process. At different stages of wound healing, the pH in the wound bed changes from slightly alkaline to neutral to acidic. To develop novel pH‐sensitive antibacterial hydrogel dressings, Zn2+‐loaded poly(2‐hydroxyethyl acrylate/itaconic acid) hydrogels are synthesized. The hydrogels exhibit pH‐sensitive swelling in the physiologically relevant pH range, with a pronounced swelling ability at neutral pH. The controlled release of Zn2+ occurs in a buffer of pH 7.40 at 37 °C. The liquid transport mechanism and release kinetics are evaluated using the specific kinetic models of Ritger‐Peppas and Peppas‐Sahlin. The effect of Zn2+ on structural, thermal, swelling, cytocompatibility, and antibacterial properties is evaluated by Fourier transform infrared spectroscopy, differential scanning calorimetry, swelling studies, MTT, and antibacterial tests. The hydrogels show excellent antibacterial activity against Escherichia coli. The research opens new perspectives for efficient wound healing management, and the extension of the study will be orchestrated by optimising the hydrogel composition to achieve improved performance.
Fast Degradable and Thermally Conductive Silicone Rubber Vitrimer with Low Dielectric and UV‐Shielding Properties
Authors: Zhang Kuan , Dang Lin , Zhang Junliang
Published: October 2023

Silicone rubbers are widely employed in various fields such as electronics, electrical engineering, mobile communications, aerospace, and automotive industries. However, silicone rubbers are typically challenging to reprocess and degrade. Moreover, with the advancement of technology, higher demands are placed on its thermal conductivity and dielectric properties. In this study, diglycidyl ether terminated polydimethylsiloxane is cured by 4,4′‐dithiodibutyric acid which contains dual dynamic covalent disulfide and ester bonds with triazobicyclodecene as the ester exchange catalyst to prepare silicone rubber vitrimers (SRVs) through a casting method. The SRVs demonstrate a relatively higher intrinsic thermal conductivity of 0.26 W (m⁻1 K⁻1) compared to ≈0.20 W (m⁻1 K⁻1) of conventional silicone rubber. Besides, the SRVs exhibit very low and stable dielectric constant and dielectric loss at both low and high frequencies (X‐band). The lowest dielectric constant and dielectric loss tangent at 10 GHz are 2.75 and 0.0650, respectively. Besides, the dual dynamic covalent bonds enable the SRVs to have excellent reprocessability and fast degradability. Moreover, the SRVs reveal UV‐shielding capability, as the transmittance of the SRVs is 0% from 200 to 400 nm of UV light.
Smart Technologies and Transition to the Circular Economy: A European Scenario in SMEs
Authors: Marino Alfonso , Pariso Paolo , Picariello Michele
Published: October 2023

The transition toward the circular economy of European small and medium‐sized enterprises (SMEs) is one of the focuses of the Agenda in Europe. The paper aims to evaluate if this drive should transform the SMEs and keep European production sustainable and competitive. The paper offers a comparative analysis of the circular economy SMEs shift within the 13 sectors of EU Member States, that have involved innovative SMEs and have begun to use or have long adopted smart technologies for the needs of control, effectiveness, efficiency, and environmental protection and energy aspect. The study highlights and evaluates the transition in 13 sectors with the highest SMEs performance with a major specialization in Smart Technologies. Five key points are identified and evaluated to analyze, the transition degree of every sector toward the circular economy. The research shows a heterogeneous transition with both sectors and countries during which the existence of best practices, are discovered, but cannot be transmitted to other sectors. A series of deterrents to the transition from a linear to a circular economy is composed within the SMEs sectors, specifically technical, commercial, and regulatory.
Use of Organic Dyes to Color the Metakaolin‐Based Geopolymer: A Physico‐Chemical Characterization
Authors: Angelo Antonio D’ , Arconati Vincenzo , Vertuccio Luigi , Viola Veronica , Catauro Michelina
Published: October 2023

Geopolymers or inorganic aluminosilicate polymers have attracted great interest for their high versatility. The use of geopolymers for cultural heritage restoration purposes is mainly related to ancient buildings. No cases in the literature report the synthesis of colored geopolymers for painting or mosaic restoration. In this preliminary study, the suitability to synthesize colored geopolymers is investigated by the use of organic pH indicator solutions as dyeing agents for white metakaolin‐based geopolymers cured at 25 °C and aged for 56 days. The physicochemical properties are analyzed by Fourier‐transform infrared spectroscopy (FTIR), pH, ionic conductivity (IC), integrity, and weight loss tests.
Stabilization Effects of Silica Nanoparticles in SIS Matrix
Authors: Zaharescu Traian , Blanco Ignazio , Borbath Tunde , Borbath Istvan
Published: October 2023

The stabilization effects of silica nanoparticles are investigated on styrene–isoprene–styrene matrix in the presence of silica nanoparticles by means of nonisothermal chemiluminescence for the implementation of results in the manufacture of plastics products. Three concentrations of n‐SiO2 filler (2%, 5%, and 10%) are prepared and studied. Four heating rates (5, 10, 15, and 20 °C min−1) are selected for the calculation of activation energies required for oxidation. The radiation degradation is achieved by γ‐irradiation, when the profiles of accelerated ageing are discussed. The progress in the oxidative degradation is discussed starting from the kinetic behavior of SIS/n‐SO2 systems as an example for other polymer materials that may be improved by this efficient filler.
Tire Selection for a Military Training Aircraft
Authors: Nicolin Bogdan Adrian , Nicolin Ilie
Published: October 2023

The aircraft tire is a complex, composite product of vital importance to all aircraft composed of rubber compounds (elastomers), fabric materials (nylon, aramid, or Kevlar), and steel wires (wire beads). The aircraft tire is subjected to very high mechanical stresses during parking, takeoff, and especially on landing, various thermal demands, solar radiation, the action of ozone, and partial discharge of the electrostatic charges accumulated on the outer surface of the aircraft. From the construction point of view, tires are bias tires or radial tires. Most aircraft tire companies recommend inflating their tires with nitrogen because it keeps out moisture, protects against corrosion, promotes compatible pressure, and is nonflammable. The selection of aircraft tires is made according to the stress to which tires are subjected and according to the recommendations of aircraft tire companies, based on the application of the Taguchi classification and the AHP multicriteria analysis methodology.
Compensation of the Shrinkage Behavior Occurring in Cylindrical Components in the FDM Process
Authors: Koers Thorsten , Magyar Balázs
Published: October 2023

Fused deposition modeling (FDM) is an additive manufacturing process that can be used to manufacture three‐dimensional thermoplastic components layer by layer. One disadvantage of FDM is the shrinkage of the components during the manufacturing process. The filament is molten in the nozzle, deposited layer by layer, and cools down again. During solidification, the filament shrinks inhomogeneously in the x/y/z direction, which leads to distortion of the component geometries. Particularly with higher nominal lengths and complex local geometries, there is a need for optimization with regard to dimensional accuracy. The aim of this paper is to counteract this on the software side with global as well as local shrinkage factors. The expected shrinkage within a layer is predicted with an in‐house developed software. The geometric accuracy of the model is verified by experimental investigations on cylindrical test specimens. In these, the so‐called clover effect occurs as a result of the shrinkage. The circular shape of the deposited layer is deformed by the distortion in the x–y plane comparable to a clover. Finally, the results are validated by analyzing a demonstrator in the form of a bracket.
Finite Element Modeling of a Biological Composite Structure Used in Orthodontic Fixed Appliances
Authors: Milicescu Stefan , Nitoi Dan , Mihai Vasile , Chivu Oana , Opran Constantin G. , Nicoară Adrian Ionut
Published: October 2023

Composite structures currently represent combinations of materials from the most different structures, chemical compositions, or geometric shapes. There is no scientific or technical field in which these materials, due to their special characteristic properties, are not present. Most of the time it is found that they cannot even be replaced. In this sense, the study presented in this work refers to the behavior of a semibiological structure. This structure is found in the field of dentistry when using fixed dental appliances. The composite structure refers to the metal bracket that is fixed by a bonding and a resin layers that are considered as adhesives to the outer surface of the tooth, i.e., to the enamel that is a biological material. In order to make a prediction of the behavior of structure during the mastication process from the point of view of the displacements and the state of tension, study starts from the practical realization of a joint by gluing the bracket on the surface of a devitalized tooth. Based on it, modeling using the finite element method allows the prediction of masticatory forces based on the analysis of stress states and displacements.
Efficiency of Simulated Annealing Algorithms Used for Improving the In‐Plane Stiffness of Inkjet Printed Composites
Authors: Vasile Alexandru , Coropeţchi Iulian Constantin , Constantinescu Dan Mihai , Sorohan Ştefan. , Picu Catalin Radu
Published: October 2023

The simulated annealing (SA) method is used in this work as to optimize the in‐plane stiffness of composite materials. Various configurations of the composite differ by the spatial distribution of hard voxels. The microstructure is assumed to be periodic, with a given length of periodicity in voxels in each of the two directions. The solution is obtained using the PyAnsys software under an MIT License, which is a collection of Python packages that enable the usage of ANSYS products. The SA algorithms prove to be very efficient, as they result in obtaining the one of the first three maximum values for the stiffness objective function for at least 98 out of 100 random trials. Therefore, SA can be successfully used for the microstructural design of composites at a fraction of the computational cost required by the brute force approach.
Mathematical Model for the Assessment of the Effect of Fiber Content on the Mechanical Properties of Phenolic Composite Reinforced Date Palm Fiber
Authors: Maou Khaoula , Belloufi Abderrahim , Abdelkrim Mourad , Maior Ioana , Opran Constantin Gheorghe
Published: October 2023

This work presents the preparation process of composite from date palm fibers and Phenolic as a matrix by compression molding. The composites are prepared with a different weight fraction of fiber from 40 to 60 wt%. The enhancement of the mechanical properties is related to the good interaction and adhesion between the filler and the matrix which is estimated by analyzing the mechanical properties of the produced composite using diverse mathematical models as Hirsch, Pukanszky, and Schrager. The results reveal that the fiber loading has a great influence on the improvement of Young's modulus and tensile strength of the Phenolic compared to the neat Phenolic. The results also show that the Hirsch model is valid for the evaluation of the elastic modulus of treated date palm fibers (TDPFs) Phenolic (PH) composites with R2 = 0.97. Regarding the evaluation of the tensile strength of Phenolic composites, it appears clear that the Pukanszky and Schrager models are adaptable for the UDPFs/PH composites. However, the Pukanszky model is not suitable for the TDPFs/PH composites.
Numerical Study of Ultrasonic Guided Wave in Composite Reinforced Panels with Different Stiffener Shapes
Authors: Antonio Antonio , Rezazadeh Nima , Polverino Antonio , Beneduce Stefano
Published: October 2023

The aim of this work is to propose a numerical methodology based on the finite element (FE) method to study the propagation mechanisms of transmitted, converted, and reflected guided waves in stiffened fiber‐reinforced polymeric (FRP) composite structures. The dispersion curves of such modes can help designers to improve the damage detection sensitivity of Lamb waves based structural health monitoring (SHM) systems. Using a FE model, whose accuracy is demonstrated against semi‐analytical data in a previous work, the phenomena of scattering and mode conversion in composite panels characterized by a structural discontinuity, such as a stiffener, are investigated. In particular, the behavior of guided waves is analyzed using stiffeners of different shapes, C and Omega shaped. The research activity makes it possible to highlight conversion of modes and reflected waves at stiffeners, providing new observations compared to the state of the art. The morphological complexities of the structure (thickness steps, multiple boundaries, stiffeners) can be used to redirect guided waves and to allow monitoring of a specific area. Wave reflections interacting with stiffeners, therefore, can be analyzed to improve diagnostics or design new detection strategies.
Effects of ethylenediaminetetraacetic acid on growth and survival of long-spined sea urchin Diadema antillarum larvae
Authors: Hassan Md Mahbubul , Pilnick Aaron R. , Patterson Joshua T.
Published: October 2023

Objective

The presence of heavy metals in seawater is a major challenge for hatchery culture of sea urchin larvae due to their sensitivity to metal pollution. The impact of heavy metals in seawater for sensitive marine larviculture could be minimized via chelation of metals using chemical compounds such as ethylenediaminetetraacetic acid (EDTA).

Methods

In this study the effects of EDTA were tested for the long-spined sea urchin Diadema antillarum during larviculture at two concentrations (10 μM and 50 μM) and two exposure durations (6 and 24 days postfertilization). Growth and survival of larvae were evaluated as response variables.

Result

Significant differences in growth and survival of larvae were found among the treatments at different EDTA concentrations and exposure durations. The 10-μM EDTA treatment enhanced growth and survival of larvae relative to control for both exposure durations. The 50-μM EDTA treatment was unsuitable for long-spined sea urchin larviculture due to reductions in growth and survival.

Conclusion

The use of 10 μM EDTA during embryo incubation and larviculture is expected to improve long-spined sea urchin larval fitness, leading to improved hatchery production.
Improved reproducibility of γ‐aminobutyric acid measurement from short‐echo‐time proton MR spectroscopy by linewidth‐matched basis sets in LCModel
Authors: Xiao Ying , Lanz Bernard , Lim Song‐I , Tkáč Ivan , Xin Lijing
Published: October 2023

γ‐Aminobutyric acid (GABA), as the primary inhibitory neurotransmitter, is extremely important for maintaining healthy brain function, and deviations from GABA homeostasis are related to various brain diseases. Short‐echo‐time (short‐TE) proton MR spectroscopy (1H‐MRS) has been employed to measure GABA concentration from various human brain regions at high magnetic fields. The aim of this study was to investigate the effect of spectral linewidth on GABA quantification and explore the application of an optimized basis‐set preparation approach using a spectral‐linewidth‐matched (LM) basis set in LCModel to improve the reproducibility of GABA quantification from short‐TE 1H‐MRS. In contrast to the fixed‐linewidth basis‐set approach, the LM basis‐set preparation approach, where all metabolite basis spectra were simulated with a linewidth 4 Hz narrower than that of water, showed a smaller standard deviation of estimated GABA concentration from synthetic spectra with varying linewidths and lineshapes. The test–retest reproducibility was assessed by the mean within‐subject coefficient of variation, which improved from 19.2% to 12.0% in the thalamus, from 27.9% to 14.9% in the motor cortex, and from 9.7% to 2.8% in the medial prefrontal cortex using LM basis sets at 7 T. We conclude that spectral linewidth has a large effect on GABA quantification from short‐TE 1H‐MRS data and that using LM basis sets in LCModel can improve the reproducibility of GABA quantification.
Lower muscle protein synthesis in humans with obesity concurrent with lower expression of muscle IGF1 splice variants
Authors: Freitas Eduardo D. S. , Kras Katon A. , Roust Lori R. , De Filippis Elena A. , Kimball Scot R. , Buras Matthew , Katsanos Christos S.
Published: October 2023

Objective

This study tested the hypothesis that expression of insulin‐like growth factor 1 (IGF‐1) protein and mRNA splice variants is lower in skeletal muscle of humans with obesity who have a lower mixed‐muscle protein fractional synthesis rate (MMP‐FSR) when compared with individuals without obesity.

Methods

The study included nine participants with obesity (OB, mean [SD],  BMI = 35 [3] kg/m2, MMP‐FSR = 0.06%/h [0.02%/h]) and nine participants without obesity (W‐OB, BMI = 24 [3] kg/m2, MMP‐FSR = 0.08%/h [0.02%/h]; for both BMI and MMP‐FSR p < 0.05). MMP‐FSR and mitochondrial protein FSR were measured following an overnight fast.

Results

Along with lower MMP‐FSR, OB participants displayed lower mitochondrial protein FSR (p = 0.03) compared with W‐OB participants. Expression of IGF‐1 (p = 0.04) and IGF‐1 receptor (p < 0.01) proteins was lower in muscle of OB participants. In addition, OB participants had lower (p < 0.05) mRNA expression of IGF1 variants Eb and Ec. This study demonstrates that lower protein synthesis in muscle of humans with obesity occurs concurrently with lower expression of muscle IGF‐1 and IGF‐1 receptor proteins, as well as lower mRNA expression of the IGF1 splice variants.

Conclusions

These findings indicate that lower protein synthesis observed in muscle of humans with obesity may result from diminished muscle IGF1 gene expression.
Fabricating UHMWPE‐based shielding materials with excellent high‐temperature mechanical properties and irradiation endurance properties via controlling crosslinked and crystalline structures
Authors: Xu Ran , Zhou Cuiqing , Sun Xiaopei , Yang Jing , Wu Ying , Pan Xiaoqiang , Chen Yang , Heng Zhengguang , Zou Huawei
Published: October 2023

Shielding materials are important guarantees for the reliable operation of nuclear equipment and essential prerequisites for the safe application of nuclear energy. As an essential and most widely used shielding material, improving the high‐temperature mechanical properties of PE‐based shielding material is of significant importance for the lightweight and integrated design of nuclear shielding material systems. Here, a simple crosslinking method was proposed to control the crosslinking degree and crystallinity to prepare UHMWPE‐based shielding materials with excellent high‐temperature mechanical properties and irradiation endurance properties. The enhancement mechanisms of mechanical properties, irradiation endurance properties and shielding properties were revealed. Meanwhile, the γ‐rays and neutrons shielding properties were studied using Geant4. When the crosslinking degree was 20.62 × 10−3 g/mol and the crystallinity was 12.13%, UHMPE‐based shielding material with optimal overall performance was obtained. Compared with the un‐crosslinked control sample, the tensile strength and elongation at break at room temperature, 70 and 90°C were 22.3 MPa (48.90% increased) and 8.43% (154.68% increased), 8.65 MPa (105.46% increased) and 6.35% (154.00% increased), 7.48 MPa (128.75% increased) and 6.2% (89.60% increased), respectively. The vicat softening temperature and maximum thermal deformation temperature were enhance 4.20 and 6.56°C when the crosslinking degree was 27.51 × 10−3 g/mol and the crystallinity is 10.83%. Our work provided a feasible method to increase the upper temperature limit and broaden the application range of PE‐based nuclear shielding materials.
High‐resolution and quantitative spatial analysis reveal intra‐ductal phenotypic and functional diversification in pancreatic cancer
Authors: Michiels Ellis , Madhloum Hediel , Van Lint Silke , Messaoudi Nouredin , Kunda Rastislav , Martens Sandrina , Giron Philippe , Olsen Catharina , Lefesvre Pierre , Dusetti Nelson , EL Mohajer Leila , Tomasini Richard , Hawinkels Lukas JAC , Ahsayni Farah , Nicolle Rémy , Arsenijevic Tatjana , Bouchart Christelle , Van Laethem Jean‐Luc , Rooman Ilse
Published: October 2023

A ‘classical’ and a ‘basal‐like’ subtype of pancreatic cancer have been reported, with differential expression of GATA6 and different dosages of mutant KRAS. We established in situ detection of KRAS point mutations and mRNA panels for the consensus subtypes aiming to project these findings to paraffin‐embedded clinical tumour samples for spatial quantitative analysis. We unveiled that, next to inter‐patient and intra‐patient inter‐ductal heterogeneity, intraductal spatial phenotypes exist with anti‐correlating expression levels of GATA6 and KRASG12D. The basal‐like mRNA panel better captured the basal‐like cell states than widely used protein markers. The panels corroborated the co‐existence of the classical and basal‐like cell states in a single tumour duct with functional diversification, i.e. proliferation and epithelial‐to‐mesenchymal transition respectively. Mutant KRASG12D detection ascertained an epithelial origin of vimentin‐positive cells in the tumour. Uneven spatial distribution of cancer‐associated fibroblasts could recreate similar intra‐organoid diversification. This extensive heterogeneity with functional cooperation of plastic tumour cells poses extra challenges to therapeutic approaches. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
Relationship between muscle thickness measured by ultrasound and physical functions: A 2‐year follow‐up study of allogeneic hematopoietic stem cell transplantation recipients
Authors: Ito Kumiko , Tada Yuma , Suzuki Masayuki , Hashida Nao , Kato Yuji , Yokota Takafumi , Ishikawa Jun , Tamiya Hironari
Published: October 2023

Background

Allogeneic hematopoietic stem cell transplantation (allo‐HSCT) is a potentially curative treatment for hematological malignancies. Several complications following allo‐HSCT, such as graft‐versus‐host disease, infection, and malnutrition, often cause physical dysfunction, and the assessment of physical function and evaluation of muscle mass are incompletely performed. Use of ultrasound (US) allows muscle mass measurement in patients with poor general conditions. In allo‐HSCT recipients, the correlation between physical function and muscle thickness, as measured by US, remains unclear.

Objective

To clarify whether muscle thickness measured by US correlated with physical function in allo‐HSCT recipients.

Design

A single‐center prospective cohort study.

Setting

Hospital.

Patients

Ninety‐two patients underwent allo‐HSCT at our hospital from April 2017 to March 2019.

Interventions

Not applicable.

Main Outcome Measure(s)

Biceps and quadriceps muscle thickness measured by US, grip strength, isometric muscle strength (elbow flexion and knee extension), and 6‐minute walking test (6MWT) before allo‐HSCT and on days 30, 90, 180, 1 year, and 2 years after allo‐HSCT. The implementation rates of these assessments were also investigated.

Results

Correlations were observed between biceps thickness and elbow flexion muscle strength/grip strength before allo‐HSCT, on days 30, 90, 180, 1 year, and 2 years after allo‐HSCT (r = 0.71/0.74, 0.73/0.72, 0.70/0.79, 0.67/0.75, 0.72/0.75, and 0.85/0.79, respectively, all p < .001). At the same time points, quadriceps thickness moderately correlated with knee extensor strength (r = 0.49, 0.50, 0.45, 0.64, 0.61, and 0.58, all p < .001). However, biceps and quadriceps thicknesses did not correlate with the 6MWT. The percentages of patients measured with US and 6MWT were 93.4% and 82.4% (p = .01) on day 30 and 97.5% and 87.8% (p = .02) on day 90, respectively.

Conclusions

US assessment may be a useful alternative method for estimating muscle strength in fragile allo‐HSCT recipients, particularly when physical function assessment is difficult to quantify.
Best practices for using electrical resistivity tomography to investigate permafrost
Authors: Herring Teddi , Lewkowicz Antoni G. , Hauck Christian , Hilbich Christin , Mollaret Coline , Oldenborger Greg A. , Uhlemann Sebastian , Farzamian Mohammad , Calmels Fabrice , Scandroglio Riccardo
Published: October 2023

Electrical resistivity tomography (ERT) is a minimally invasive geophysical method that produces a model of subsurface resistivity from a large number of electrical resistance measurements. Strong resistivity contrasts usually exist between frozen and unfrozen earth materials, making ERT an effective and increasingly utilized tool in permafrost research. In this paper, we review more than 300 scientific publications dating from 2000 to 2022 to identify the capabilities and limitations of ERT for permafrost applications. The annual publication rate has increased by a factor of 10 over this period, but several unique challenges remain, and best practices for acquiring, processing, and interpreting ERT data in permafrost environments have not been clearly established. In this paper, we make recommendations for ERT surveys of permafrost and highlight recent advances in the field, with the objective of maximizing the utility of existing and future surveys.
The SPEC score—A quantifiable CT scoring system for primary ciliary dyskinesia
Authors: Chowdhary Tarika , Bracken Jennifer , Morgan Lucy , Schultz Andre , Robinson Phil
Published: October 2023

Background

Structural lung changes seen on computed tomography (CT) scans in persons with primary ciliary dyskinesia (pwPCD) are currently described using cystic fibrosis (CF) derived scoring systems. Recent work has shown structural changes and frequencies that are unique to PCD, indicating the need for a unique PCD‐derived scoring system.

Methods

Chest CT scans from 30 pwPCD, were described for structural changes including bronchiectasis, bronchial wall thickening, mucous plugging, atelectasis, air trapping, and interlobar septal thickening and, additionally, changes previously described as being frequent in pwPCD including extensive tree‐in‐bud pattern of mucous plugging, bronchoceles or nodules, thickening of interlobar and interlobular septa and whole lobe atelectasis. Based on these findings a novel and unique scoring system, the Specific PCD Evaluation by CT (SPEC) score was constructed. Scans were then re‐scored using the SPEC score and results compared to corresponding measurements of lung function to assess structure‐function correlation.

Results

Total SPEC scores ranged from 0 to 60 (max possible score 90). There was a strong negative correlation between the SPEC score (SPEC) and forced vital capacity (FVC), forced expiratory volume over 1 s (FEV1) and FEV1/FVC ratio (−r = .784, −.865, −.872 respectively).

Conclusions

Using PCD‐derived data we describe the construct of a PCD‐specific score for assessing lung structural damage on CT scans, the SPEC score. A strong correlation between the SPEC score and PFT variables was identified. The SPEC score holds the potential for describing longitudinal changes in CT scans and assessing the efficacy of interventive therapies in patients with PCD.
Control of sweet potato whitefly (Bemisia tabaci) using entomopathogenic fungi under optimal and suboptimal relative humidity conditions
Authors: Bohatá Andrea , Folorunso Ewumi Azeez , Lencová Jana , Osborne Lance S , Mraz Jan
Published: October 2023

BACKGROUND

Sweet potato whitefly (Bemisia tabaci) is one of the most destructive pests to an extensive range of crops and vegetables. Pesticide‐dependent management programs have led to severe health problems, including pesticide poisoning and cancer in human beings, as well as pesticide resistance in insect pests. Entomopathogenic fungi (EPF) are considered safe and highly effective against many pests. Therefore, identifying the pathogenicity and virulence of EPFs against Bemisia tabaci is a valuable addition to the management of their infestations. In this study, we investigated the efficacy of conidia suspensions of Aschersonia aleyrodis, Isaria fumosorosea, Beauveria bassiana, and Akanthomyces muscarius (= Lecanicillium muscarium) against nymphal stages of Bemisia tabaci in cucumber seedlings under both optimal and suboptimal conditions.

RESULTS

All of the EPFs demonstrated significant ovicidal effects, with the highest cumulative mortalities observed in Aschersonia aleyrodis (96.46%) and I. fumosorosea‐treated (94.60%) seedlings against host eggs and crawlers. Similarly, in the L4‐instars experiment, Aschersonia aleyrodis and I. fumosorosea were the most efficient, resulting in cumulative mortalities of 94.82% and 94.75%, respectively. However, Bemisia tabaci cumulative mortalities on seedlings treated with Akanthomyces muscarius (78.36%) and Beauveria bassiana (85.90%) were also significantly different from untreated seedlings (7.10%). Under suboptimal relative humidity (RH) conditions (≤ 45% RH), Aschersonia aleyrodis exhibited greater tolerance to harsh conditions, causing a significantly higher infection rate in L1–L2 nymphs (~92%) compared to the approximately 32% infected young nymphs observed in I. fumosorosea‐treated seedlings.

CONCLUSION

All the selected EPF were more effective against the young nymphal instars. Our results also highlight the efficacy of Aschersonia aleyrodis under suboptimal conditions. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Integrating machine learning with pharmacokinetic models: Benefits of scientific machine learning in adding neural networks components to existing PK models
Authors: Valderrama Diego , Ponce‐Bobadilla Ana Victoria , Mensing Sven , Fröhlich Holger , Stodtmann Sven
Published: October 2023

Recently, the use of machine‐learning (ML) models for pharmacokinetic (PK) modeling has grown significantly. Although most of the current approaches use ML techniques as black boxes, there are only a few that have proposed interpretable architectures which integrate mechanistic knowledge. In this work, we use as the test case a one‐compartment PK model using a scientific machine learning (SciML) framework and consider learning an unknown absorption using neural networks, while simultaneously estimating other parameters of drug distribution and elimination. We generate simulated data with different sampling strategies to show that our model can accurately predict concentrations in extrapolation tasks, including new dosing regimens with different sparsity levels, and produce reliable forecasts even for new patients. By using a scenario of fitting PK data with complex absorption, we demonstrate that including known physiological structure into an SciML model allows us to obtain highly accurate predictions while preserving the interpretability of classical compartmental models.
Estimation of streamflow of the ungauged mountainous watersheds of the Western Ghats in India using the SWAT model
Authors: George Celine , James E. J.
Published: October 2023

The Western Ghats in the humid tropical zone of Kerala State, India have several drinking water, irrigation and hydroelectric projects, which exclusively depend on streamflow. The seasonal monsoon rainfall imposes several limitations in estimating the streamflows. The rugged topography of these highland areas with thick forest vegetation restricts the installation of conventional gauging stations. Considering these factors, an attempt is made to estimate the streamflow from these watersheds using the Soil and Water Assessment Tool model. Eight representative watersheds with stream gauging stations were selected, of which six were used for initial calibration, validation of the model and identifying the model parameters to be regionalised. The regionalised model was then applied to the other two watersheds, and the estimated data were compared with the observed. Global average, regression method and common parameter transfer approaches were adopted to regionalise the parameters. The calibrated model parameters are averaged in the global average method. The regression function in the data analysis add‐on in the Excel platform determined the functional relationship between the watershed characteristics and the model calibration parameters. The parameter transfer helped recognise two standard sensitive parameters. It is found that by providing the topography, land use and soil data, the streamflow from the ungauged watersheds of the highland belt in the wet humid tropical zone of Kerala can be satisfactorily simulated.