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Parasitism is known to affect the behavior of host species to enhance parasite dispersal and transmission. However, host behavioral responses to parasitism unrelated to parasite dispersal and transmission have been much less studied. The objective of this study was to determine whether grasshopper hosts infected and uninfected with a parasitic fly (Blaesoxipha sp.) differ in terms of the nutrient content of the diet they consume. We investigated the dietary preferences of two grasshopper species (i.e. Asulconotus chinghaiensis and Chorthippus fallax) in terms of the C/N composition of plant species consumed, and determined whether this affected the egg production of unparasitized and parasitized grasshoppers by flies in a Tibetan alpine meadow. The composition of plants consumed differed significantly between the unparasitized and parasitized grasshoppers. Specifically, the abundance of N‐rich legumes was lower and that of high C/N grasses was higher in the diet of the parasitized compared to the unparasitized grasshoppers. Diet N content was higher and C/N was lower in the diet of unparasitized grasshoppers, and parasitized females produced fewer eggs than their unparasitized conspecifics. Future enquiries are needed to understand the specific mechanisms underlying these dietary differences. The effects of parasites on the fitness–associated behavior of hosts should be studied more broadly to better understand parasite evolution and adaptation. [ABSTRACT FROM AUTHOR]

Scholars have explored the factors influencing new product adoption from various perspectives, such as product characteristics, personality traits, and marketing communication strategies. However, these studies lack the consideration of consumer social relationships. Thus, this study examined how social exclusion influences new product adoption. Three experiments involving 1372 participants indicated that social exclusion leads to a higher really new products adoption compared to social inclusion. The mediating factor in this relationship is the need for uniqueness. In contrast, no significant difference in incrementally new product adoption was found between socially excluded and included individuals. The above effects only exist in individuals with low self‐control. Individuals with high self‐control exhibit no significant difference in RNP adoption intention, whether they experience social exclusion or inclusion. These findings not only significantly increase the body of knowledge on social exclusion and new products, but also advise marketers on how to promote new products. [ABSTRACT FROM AUTHOR]

Photooxidation aging, hygrothermal aging, and hot‐air aging are carried out on atactic polystyrene (aPS) samples formed by injection molding. It is interesting that microcrystals of atactic polystyrene are only found in photooxidation aging. This work proposes that high molecular weight atactic polystyrene can crystallize under photooxidation aging. It is a good addition to the research on the aspect of crystallization of atactic polystyrene. [ABSTRACT FROM AUTHOR]

We present a finite volume scheme for 2D steady convection–diffusion equations on arbitrary convex polygonal meshes. The method uses auxiliary unknowns on the cell‐edge and cell‐node of the mesh, and the continuous flux is computed to be a two‐point nonlinear flux. Since the transpose of the coefficient matrix is an M‐matrix, it is guaranteed that the scheme is positive. We propose a new strategy, which aims that providing a scheme without separated method to compute the value on the cell‐edge without previous reconstruct. Numerical results show that our scheme is positive on polygonal meshes for both diffusion‐dominated and convection‐dominated problems and has second‐order accuracy for solutions. [ABSTRACT FROM AUTHOR]

The aim of this study was to improve the mechanical performance of biodegradable poly(L‐lactic acid) through equal channel angular extrusion (ECAE). Changes in morphology induced by the ECAE shear deformation in poly(lactic acid) (PLA) were investigated. Differential scanning calorimeter results suggested a significant improvement in crystallinity of ECAE‐deformed PLA depending on its thermal condition and deformation force. Two‐dimensional wide angle X‐ray diffraction measurement and polarized FTIR spectroscopies of ECAE‐deformed PLA revealed a structural network in the crystalline region, and the taut tie molecules (TTMs) connecting lamellae also stretched. Scanning electron microscope results showed that the macro‐fibrils were generated, and the oriented structures were arranged along the nominal shear direction at a certain angle. Both the inclined macro‐fibrils structure and the oriented TTMs within fibrils were beneficial in improving mechanical performance. Finally, the mechanical property tests showed that the mechanical properties of PLA were improved overall. The tensile strength, elongation, impact strength, and bending strength increased by 28%, 123.8%, 224.3%, and 47.6%, respectively. Meantime, a transition from brittle fracture to ductile fracture was observed from the original PLA billet to ECAE‐deformed one. Therefore, the ECAE process represents a promising approach for comprehensively reinforced PLA. [ABSTRACT FROM AUTHOR]

Dietary differences are often observed among generalist herbivores co‐occurring in the same community. However, the factors underlying the differences remain poorly understood. In the context of insect herbivores, we hypothesized that interspecific dietary differences are associated with life history traits. Specifically, we hypothesized that the size of wings as well as gender participate in defining dietary preferences, that is, long‐winged species and males will tend to forage on plants with high C/N to maximize dispersal and mating, whereas short‐winged species and females will forage on N‐rich plants to maximize egg production. We tested this hypothesis by examining the diets of the males and females of three long‐winged and two short‐winged grasshopper species in an alpine meadow. The dietary composition and relative abundance of each species were determined using DNA meta‐barcoding. The data showed that the consumed plant species were similar among all of the grasshopper species and between the males and females. However, quantitative differences in the diets were significant between the long‐winged and short‐winged guilds and between the males and females of each species. Consistent with the hypothesis, (1) the long‐winged species fed more on monocots with high C/N, whereas the short‐winged species fed more on legumes with high N contents, (2) for each short‐winged species the males fed more on monocots with high C/N compared to the females, and (3) across all grasshopper species, egg numbers were positively associated with the weighted dietary N. These data indicate that the dietary preferences of these generalist grasshoppers are associated with life history tradeoffs. [ABSTRACT FROM AUTHOR]

Background: Identification of small pulmonary nodules is challenging in a limited intrathoracic field during minimally invasive video‐assisted thoracoscopic surgery (VATS), and preoperative localization is required. Various techniques have been reported with some failure and complications. Here, we compare the feasibility and safety between electromagnetic navigation bronchoscopic marking and computed tomography (CT)‐guided percutaneous marking using indocyanine green (ICG) and iopamidol. Methods: A total of 47 patients with small‐sized pulmonary nodules, scheduled to undergo video‐assisted thoracoscopic limited resection, were enrolled in this study. A mixture of diluted ICG and iopamidol was injected into the lung parenchyma as a marker, using CT‐guided percutaneous or electromagnetic navigation bronchoscopic injection techniques and the results were examined and compared. Results: A total of 35 and 12 patients underwent preoperative marking by percutaneous injection and electromagnetic navigation bronchoscopic injection, respectively, in which a marker was detected in 33/35 (94.3%) and 12/12 (100%) patients. No combination of these procedures was performed in any patient. All markers were successfully detected in three patients who underwent injection marking at two different lesion sites. Pneumothorax occurred in five patients (14%) in the percutaneous marking group, which was relieved in all patients without the necessity for chest tube drainage. No other complication was observed in this study. Conclusions: Electromagnetic navigation bronchoscopic injection techniques using indocyanine green fluorescence plus iopamidol are safe and effective, and comparable with CT‐guided localization. Furthermore, a bronchoscopic approach enables marking of multiple lesion areas without increasing patient risk, especially for puncture‐related pneumothorax. Key points: Significant findings of the study: Either computed tomography (CT)‐guided percutaneous or electromagnetic navigation bronchoscopic injection techniques can be used for preoperative marking of pulmonary nodules with indocyanine green (ICG) fluorescence. What this study adds: Indocyanine green (ICG) is a safe and easily detectable fluorescent marker for video‐assisted thoracoscopic surgery (VATS).A bronchoscopic injection approach enables marking of multiple lesion areas without increasing the risk of pneumothorax. [ABSTRACT FROM AUTHOR]

Purpose: As a novel imaging modality, x‐ray fluorescence computed tomography (XFCT) can provide distribution and concentration information of contrast agents containing high atomic number elements, such as iodine, gadolinium, barium, gold, and platinum. Since XFCT has a better sensitivity and detection limit of high‐Z elements compared with traditional and spectral CT, it becomes a powerful quantitative imaging tool for biological studies. The main problem of current XFCT imaging is its low emission and detection efficiency of x‐ray fluorescence (XRF) photons. Increasing XRF photons generation by choosing a high atomic element as a contrast agent is essential to improve the imaging quality of XFCT. Gadolinium emits at least a few times more of XRF photons than gold under the same x‐ray excitation condition, leading to a detection limit at a level of sub‐mg/mL as the next generation of clinical imaging modality. However, most current XFCT studies have utilized gadolinium salt as the contrast agent, which could not accumulate in organs or tumors efficiently, making in vivo XFCT imaging quite difficult. In this study, we present NaGdF4 nanoparticles with ultra‐small size as nanoprobes to test the feasibility for in vivo XFCT application for the first time. Methods: NaGdF4 nanoparticles with different sizes (3–10 nm) were successfully synthesized via a coprecipitation process by controlling the reaction time at temperature of 290 °C. The morphology, crystal phase, chemical composition, and size of such NPs were further characterized with HR‐TEM, XRD, and EDX. The abilities of XRF photons from different sizes of NPs were quantified by our customized XFCT imaging system. To access the in vivo application of as‐synthesized NPs, such hydrophobic NPs capped OA molecules were further modified with AEP via a ligand‐exchange process and characterized with FT‐IR. For in vivo XFCT imaging, 0.1 mL of 30 mg/mL NPs were injected into nude mice via the tail vein. The Varian G‐297 x‐ray tube was set to 150 kV and 0.5 mA. The XRF photons were captured by a Kromek eV‐3500 photon counting detector at each 8° for 10 s. Result: The successfully synthesized NaGdF4 nanoparticles (3–10 nm) were monodisperse, highly uniform spherical morphology and hexagonal crystalline phases. No significant influence on XRF photons yields or XFCT imaging quality were found by varying the nanoparticle size. The XRF photons were 2.5 times more emitted from NaGdF4 nanoparticles (NPs) compared to gold nanoparticles, thereby leading to a better image quality. With the AEP surface modification, such NPs were readily adapted for use in in vivo XFCT applications with monodispersity in aqueous solution and negligible cytotoxicity. With the tail‐vein injection, the liver, spleen, and lungs could be clearly imaged with XFCT at a sub‐mg/mL level. Conclusions: Such NaGdF4 NPs, which were synthesized with coprecipitation process, were modified with AEP for in vivo XFCT applications. With both the phantom and in vivo experiments, such NPs were proved to be appropriate probes for XFCT application with the detection limit at a sub‐mg/mL level. In the future research, such NPs could be further functionalized with targeting molecules for early‐phase cancer detection. [ABSTRACT FROM AUTHOR]

A new positive finite volume scheme for the two‐dimensional convection‐diffusion equation on deformed meshes is proposed. The approximation of the convective flux is based on some available information of the diffusive flux. The scheme can keep local conservation of normal flux on the cell‐edge and can be used to deal with the case that the diffusive coefficients are discontinuous and anisotropic. In addition, no limiter is introduced. For the unsteady problem, the existence of a solution for the nonlinear discrete system is proved. Numerical results show that the new scheme has second order accuracy and can preserve the positivity. [ABSTRACT FROM AUTHOR]