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Single crystals of La2CaB10O19(LCB), a new nonlinear optical material have been successfully grown from a CaB4O7–La2CaB10O19 solution using the top-seeded method. The LCB crystal grows in the shape of a thick-tabular rhombus along with the extension of the a–b crystal plane. The b-direction of LCB is parallel to the short diagonal of the rhombus. [Copyright &y& Elsevier]

In this paper, a reverse-bootstrap turboexpander-compressor (TEC) scheme is proposed for the direct recovery of expansion work into the cooling capacity of small air-separation plants. A mathematical model is established for the codesign and off-design analysis of TEC. The off-design performance is predicted based on the mean streamline method and is validated by the experimental data. The isentropic coefficient is proposed to evaluate the overall performance improvement of the reverse-bootstrap TEC. The results indicate that the use of a reverse-bootstrap compressor in the original turboexpander can increase the isentropic coefficient by 12% compared with that of the traditional braking turboexpander under design condition. The codesign of the turboexpander and the coaxial compressor can improve the coupling characteristics and further increase the isentropic coefficient by 7.1% under design condition, which shows cooling power improvement by 8.1% and reduction of required heating power by 1.7%. The results and analysis demonstrate that the proposed reverse-bootstrap TEC with the codesign method is an effective way for the energy recovery in small refrigeration systems. [Display omitted] • A reverse-bootstrap TEC is proposed for air-separation plants. • Codesign approach and off-design model are developed for TEC. • Interdependency of TEC operating parameters are quantitatively described. • Codesign of TEC leads improvement of TEC cooling power by 8.1%. [ABSTRACT FROM AUTHOR]

Highlights: [•] An ultrasonic aerosol spray method is used to prepare TiO2/In2O3 composite. [•] The composite photocatalyst shows excellent visible-light absorption. [•] The optimal Ti:In ratio for visible-light-driven photocatalysis is 100:1. [ABSTRACT FROM AUTHOR]

In high-altitude cold regions, the degradation of asphalt pavement surfaces is exacerbated by unique climatic conditions, including intense ultraviolet (UV) radiation and substantial temperature variations. Aging of asphalt under the combined effects of intense UV radiation and large temperature variations is a complex process, and reproducing these conditions in an indoor environment is challenging. This study aimed to investigate the aging mechanisms of asphalt under the combined effects of intense UV radiation and large temperature variations. The changes in asphalt chemical composition over time were analyzed using fractionation of saturates, aromatics, resins, and asphaltenes (SARA) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). Additionally, atomic force microscopy (AFM) was utilized to characterize the surface micro-topography and micromechanical properties of asphalt at various aging stages. The results showed that the combined aging mechanisms significantly differed from those of thermal-oxidative and UV aging. A discernible "gradient aging" phenomenon was evident in asphalt under the combined effects, with the surface layer undergoing photo-oxidation, photolysis, and polycondensation, resulting in a hard film. The sub-surface layer underwent restructuring and aggregation of asphaltenes, while the lower layer experienced decomposition of larger molecular asphaltenes, and the "migration" of smaller molecular asphaltenes to the sub-surface layer. The "gradient aging" in asphalt caused significant mechanical differences, which were crucial to the onset and development of surface cracks. Moreover, a greater modulus differential between the layers was associated with an elevated risk of cracking. This study enhances the understanding of the composite aging mechanism of asphalt, and contributes to the development of anti-aging pavement materials. • A discernible "gradient aging" phenomenon was evident in the asphalts under the combined effects of intense UV radiation and large temperature variations. • The notable differences in material properties caused by "gradient aging" are a critical factor for the surface cracking of asphalt. • The combined aging mechanisms significantly differ from thermal-oxidative and UV. • The generation and evolution mechanisms on the combined aging of the asphalt were explained from chemical composition, microstructure, and micromechanics. [ABSTRACT FROM AUTHOR]

• A dual-column distillation process is proposed for offshore nitrogen production. • Liquid nitrogen of high purity is realized under offshore conditions. • Distillation is more sensitive to tilting than swing. • Increasing swing period deteriorates distillation. Cryogenic distillation is widely acknowledged as the primary industrial method for producing liquid nitrogen of high purity. However, the distillation process is highly sensitive to tilting and swinging, which limits the application of cryogenic air separation in offshore infrastructures. This paper proposes a small-scale air separation process that incorporates a dual-column distillation to enhance distillation performance under offshore conditions. Experiments were conducted under standard (no-tilting and stationary), tilting, and swinging conditions. The results indicate that the proposed distillation plant can maintain nitrogen purity to a certain extent under offshore conditions. The product impurity (oxygen content) increased significantly as the tilting angles increased beyond 4° for horizontal titling and 3° for longitudinal titling, respectively. The distillation performance was less affected by the swing than the tilting. High-purity nitrogen could be produced when swing amplitude was within ±10° and swing period was between 6 s and 11 s. The results can provide engineering guidance for the design and installation of the columns of air-separation plants. [ABSTRACT FROM AUTHOR]

Humans are able to learn to implement novel rules from instructions rapidly, which is termed "instruction-based learning" (IBL). This remarkable ability is very important in our daily life in both learning individually or working as a team, and almost every psychology experiment starts with instructing participants. Many recent progresses have been made in IBL research both psychologically and neuroscientifically. In this review, we discuss the role of language in IBL, the importance of the first trial performance in IBL, why IBL should be considered as a goal-directed behavior, intelligence and IBL, cognitive flexibility and IBL, how behaviorally relevant information is processed in the lateral prefrontal cortex (LPFC), how the lateral frontal cortex (LFC) networks work as a functional hierarchy during IBL, and the cortical and subcortical contributions to IBL. Finally, we develop a neural working model for IBL and provide some sensible directions for future research. • Humans are able to learn from instructions rapidly, and this remarkable ability is termed instruction-based learning (IBL). • Instruction-based learning is closely related to language and fluid intelligence (g). • The multiple-demand (MD) system is essential for IBL. • Instruction-based learning involves three main stages including: acquisition, retrieval, and implementation. • A neural working model was built based on the three main stages involved in instruction-based learning. [ABSTRACT FROM AUTHOR]

For most breast cancer (BC) patients who have undergone a mastectomy, the decision whether to proceed with breast reconstruction (BR) is complicated and requires deliberation. Shared decision-making (SDM) helps to address those needs and promote informed value-based decisions. However, little is known about the SDM status for BR in BC patients. This scoping review describes: 1) basic characteristics of studies on BR SDM in BC patients; 2) factors influencing BR SDM in BC patients; 3) experience and perception of BR SDM in BC patients; and 4) outcome measures reported. This review was performed in accordance with the Arksey and O'Malley methodology. A total of 5 English and 4 Chinese databases were searched, as well as different sources from grey literature. The data extraction form was developed by referring to the objectives and the Ottawa Decision Support Framework (ODSF). Data was analyzed using thematic analysis, framework analysis and descriptive statistics, with findings presented in the tables and diagrams. A total of 1481 records were retrieved and 42 of these included after screening. In 21 (21/42, 50%) of the studies, patient decision aids (PDAs) were utilized, and in 17 (17/42, 40.48%) of the studies, the factors influencing the implementation of SDM were explored. Of these 17 studies, the factors influencing the implementation of SDM were categorized into the following: the patient level (17/17, 100%), the healthcare level (2/17, 11.76%) and the organizational and system level (7/17, 41.18%). A total of 8 (19.05%) of the 42 studies focused on patients' experiences and perceptions of SDM, and all studies used qualitative research methods. Of these 8 studies, a total of 7 (7/8, 87.50%) focused on patients' experiences of SDM participation, and 4 (4/8, 50.00%) focused on patients' perceptions of SDM. A total of 24 studies (24/42, 57.14%) involved quantitative outcome measures, where 49 items were divided into three classifications according to the outcomes of ODSF: the quality of the decision (17/24, 70.83%), the quality of the decision-making process (20/24, 83.33%), and impact (13/24, 54.17%). Although researchers have paid less attention to other research points in the field of SDM, compared to the design and application of SDM interventional tools, the research team still presents some equally noteworthy points through scoping review. For instance, the various factors influencing BC patients' participation in SDM for BR (especially at the healthcare provider level and at the organizational system level), patients' experiences and perceptions. Systematic reviews (SRs) should be conducted to quantify the impact of these different factors on BR SDM. Implementation of scientific theories and methods can inform the exploration and integration of these factors. [ABSTRACT FROM AUTHOR]

The jet-based technologies were introduced in roof directional pre-cutting, which is one of the critical technologies in the no-pillar mining method without excavating mining roadways. Based on the laboratory and field experiments, both directional hydraulic fracturing and hydraulic slotting technologies were able to form the directional fractures, and their performances were affected by cutting efficiency. Jet diffusion was affected by flow instabilities and had effects on cutting efficiency. To further enhance the cutting efficiency, numerical simulations based on the modified cavitation and turbulence models were performed to elucidate the jet diffusion mechanism, and a new type of slotter is designed to address the problems of jet diffusion and the short service life of the current original slotter. Cavitation-vortex interaction was observed in the slotter and worked together with turbulence to account for the jet diffusion. The new slotter weakened the instabilities induced by both turbulence and bubble collapse/burst, and thus suppressed the diffusion disintegration process of the jet. Compared with the conventional slotter, the diffusion angle of the new slotter is reduced by 50%, and the slotting performance is improved by 30%. The present study serves as a supplement to channel optimization, contributing to the further enhancement of pre-cutting efficiency. • Hydraulic techniques have the advantage of forming directional fractures accurately. • Jet diffusion impaired the slotting performance and pre-cutting efficiency. • A modified model was used to elaborate the jet diffusion mechanism. • New slotters weaken the flow instability and enhance the slotting performance by 30%. • A conveyor was developed independently to enhance the roof pre-cutting efficiency. [ABSTRACT FROM AUTHOR]

In this paper, simulations of supercritical heat transfer of R134a in horizontal tubes are performed to study the effects of circumferential heat conduction on the heat transfer deterioration, and the abnormal phenomena of higher temperature distribution of non-gravity supercritical flow is explained. The results show the heat transfer deterioration is caused by the impairment of specific heat and heat conduction in the boundary layer while the following recovery of heat transfer is due to the enhancement of thermal conduction and turbulent convection. A dimensionless parameter of Biot number is defined to characterize the thermal resistance ratio of the circumferential conduction to the convective heat transfer. The wall temperature redistribution due to the circumferential conduction affects the supercritical convection in horizontal tubes, and non-gravity supercritical flow may have a higher wall temperature when the Bi number is small. The deterioration of the top surface can be significantly alleviated in a tube with a larger wall thickness or thermal conductivity. • Biot number characterizes the circumferential conduction in supercritical flow. • Non-gravity flow has higher wall temperature at small circumferential Bi number. • High thermal conductivity or wall thickness alleviates heat transfer deterioration. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) is an attractive electrochromic and storage material due to its reversible and sustainable electrochemical redox processes. However, the insufficient surface area and excessive charge intercalation after long-term cycling results in limited charge capacitance and unsatisfactory cycling stability. In this work, we demonstrate an innovative method to increase PANI's electrochromic and energy storage performance by incorporating MXene, to enhance electrochemical activity and reveal more active areas of ion/electron intercalation/deintercalation and charge transfer. The hydrogen bonds formed between N-H, C-H, and C-N of PANI and -OH and -O surface functional terminations of MXene further enhance the interface interaction. With substantial optical transmittance modulation and charge capacitance, excellent coloration efficiency, and outstanding durability, the PANI/MXene thin film demonstrates exceptional color-switching and energy storage characteristics. Furthermore, the sandwich device with a PANI/MXene thin film as the positive electrode and zinc foil as the negative electrode demonstrates exceptional electrochromic and Zn 2+ storage capability. This work raises possibilities for next-generation intelligent energy conversion and storage technologies and offers fresh perspectives on the design of ionic devices., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Rosai-Dorfman disease (RDD), also known as sinus histiocytosis with massive lymphadenopathy, is an uncommon histiocytic disease with idiopathic etiology and unique pathology. Extra-nodal RDD that occurs in the nasal cavity is extremely unusual and the characteristic clinical features are unknown. Herein, we report a case of nasal septum RDD, with intermittent epistaxis from the left nasal cavity, which led to collapse of the nasal bridge. The patient underwent surgical biopsy, and a diagnosis of nasal septum RDD was established. No further treatment was performed. An enlarged mass was found in the second postoperative year which was treated by surgical excision in the third postoperative year. To improve the current diagnostic and therapeutic approach of extra-nodal RDD, we incorporate previous reports from the literature to discuss the pathological characteristics, pathogenesis, clinical manifestations, diagnosis, and therapy for this rare disease., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Efficient near-infrared (NIR) laser marking on transparent polymers like polypropylene, epoxy, and polyethylene has posed a big challenge due to their lack of absorption in the NIR. Currently, inorganic additives are used to improve NIR laser marking efficiency, but they come with issues such as toxicity, high loading requirement, adverse effects on color/opaqueness, and the need for low laser head speeds. Herein, we report a new strategy of incorporating a food-grade, Mg 2 Al-CO 3 LDH as a boosting coadditive alongside the commercial NIR laser marking additive (Iriotech 8815) in an epoxy system. Our findings demonstrate that the incorporation of Mg 2 Al-CO 3 LDH can significantly increase both the darkness and contrast of marking even at high laser head speed (5000 mm/s), while minimizing surface damage. Notably, by replacing 95% of Iriotech 8815 with Mg 2 Al-CO 3 LDH, an epoxy plate can exhibit high transparency, while producing dark, sharply defined markings with excellent readable QR code markings at high laser speeds. This result offers a promising solution for enhancing high-speed NIR laser marking on transparent polymers with additional advantages of lower toxicity and cost and with minimal optical interference from high additive loadings., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

We have studied the size-dependent optical scattering of aqueous suspensions containing Mg 2 Al-LDH platelets, which exhibit high total- and side-scatterings. By incorporating 3 wt% Mg 2 Al-LDH platelets (280 nm) in a commercial sunscreen formulation, we achieved a twofold Sun Protection Factor boost, providing a promising, high-efficient and non-toxic strategy to enhance sunscreen effectiveness.

Defect engineering has proven to be one of the most effective approaches for the design of high-performance electrocatalysts. Current methods to create defects typically follow a top-down strategy, cutting down the pristine materials into fragmented pieces with surface defects yet also heavily destroying the framework of materials that imposes restrictions on the further improvements in catalytic activity. Herein, we describe a bottom-up strategy to prepare free-standing NiFe layered double hydroxide (LDH) nanoplatelets with abundant internal defects by controlling their growth behavior in acidic conditions. Our best-performing nanoplatelets exhibited the lowest overpotential of 241 mV and the lowest Tafel slope of 43 mV/dec for the oxygen evolution reaction (OER) process, superior to the pristine LDHs and other reference cation-defective LDHs obtained by traditional etching methods. Using both material characterization and density functional theory (DFT) simulation has enabled us to develop relationships between the structure and electrochemical properties of these catalysts, suggesting that the enhanced electrocatalytic activity of nanoplatelets mainly results from their defect-abundant structure and stable layered framework with enhanced exposure of the (001) surface.

A cascade selenylation/cyclization of dienes with diselenides has been realized under visible-light irradiation or electrolysis conditions. Employing O 2 or electricity as a "green" oxidant, this protocol provides a green and efficient method for an array of biologically important seleno-benzo[ b ]azepine derivatives in moderate to good yields. The direct sunlight irradiation and gram-scale reaction render the approach practical and attractive.

Dual-band electrochromic materials (DBEMs) are of utmost importance for smart windows to realize independent control of the visible (VIS) and near-infrared (NIR) light. However, very few single-component DBEMs are capable of independently and effectively controlling both VIS and NIR light. Here, we present Prussian blue (PB) with remarkable performance to replace the composite DBEMs that require deliberate design and complicated preparation. Excellent durability and capacity were achieved simultaneously due to the activated low-spin Fe in PB. A dual-band electrochromic device (DBED) by using PB thin films as electrochromic layers was constructed, exhibiting superior dual-band electrochromic performance, energy storage performance and memory effect. We show that the energy-saving DBED can be bleached without applying any external bias potential, and can be colored by using a commercial photovoltaic solar panel under ambient solar irradiation. The stored energy during coloration can be further used to light up the lights. Finally, the coloration mechanism of the DBED was studied by the density functional theory calculations, to shed light on the large optical transmittance modulation in both VIS and NIR regions. The new insights will advance the design of efficient and durable DBEMs and the development of bi-functional smart windows., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Deep learning approaches have been widely adopted in the medical image analysis field. However, a most of existing deep learning approaches focus on achieving promising performances such as classification, detection, and segmentation, and much less effort is devoted to the explanation of the designed models. Similarly, in the brain imaging field, many deep learning approaches have been designed and applied to characterize and predict human brain states. However, these models lack interpretation. In response, we propose a novel domain knowledge informed self-attention graph pooling-based (SAGPool) graph convolutional neural network to study human brain states. Specifically, the dense individualized and common connectivity-based cortical landmarks system (DICCCOL, structural brain connectivity profiles) and holistic atlases of functional networks and interactions system (HAFNI, functional brain connectivity profiles) are integrated with the SAGPool model to better characterize and interpret the brain states. Extensive experiments are designed and carried out on the large-scale human connectome project (HCP) Q1 and S1200 dataset. Promising brain state classification performances are observed (e.g., an average of 93.7% for seven-task classification and 100% for binary classification). In addition, the importance of the brain regions, which contributes most to the accurate classification, is successfully quantified and visualized. A thorough neuroscientific interpretation suggests that these extracted brain regions and their importance calculated from self-attention graph pooling layer offer substantial explainability., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Preterm birth is a worldwide problem that affects infants throughout their lives significantly. Therefore, differentiating brain disorders, and further identifying and characterizing the corresponding biomarkers are key issues to investigate the effects of preterm birth, which facilitates the interventions for neuroprotection and improves outcomes of prematurity. Until now, many efforts have been made to study the effects of preterm birth; however, most of the studies merely focus on either functional or structural perspective. In addition, an effective framework not only jointly studies the brain function and structure at a group-level, but also retains the individual differences among the subjects. In this study, a novel dense individualized and common connectivity-based cortical landmarks (DICCCOL)-based multi-modality graph neural networks (DM-GNN) framework is proposed to differentiate preterm and term infant brains and characterize the corresponding biomarkers. This framework adopts the DICCCOL system as the initialized graph node of GNN for each subject, utilizing both functional and structural profiles and effectively retaining the individual differences. To be specific, functional magnetic resonance imaging (fMRI) of the brain provides the features for the graph nodes, and brain fiber connectivity is utilized as the structural representation of the graph edges. Self-attention graph pooling (SAGPOOL)-based GNN is then applied to jointly study the function and structure of the brain and identify the biomarkers. Our results successfully demonstrate that the proposed framework can effectively differentiate the preterm and term infant brains. Furthermore, the self-attention-based mechanism can accurately calculate the attention score and recognize the most significant biomarkers. In this study, not only 87.6% classification accuracy is observed for the developing Human Connectome Project (dHCP) dataset, but also distinguishing features are explored and extracted. Our study provides a novel and uniform framework to differentiate brain disorders and characterize the corresponding biomarkers., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhang, Wang, Wang, He, Wu, Kang, Zhang, Gao, Hu and Zhang.)

Lead-free double perovskites, A 2 M + M '3+ X 6 , are considered as promising alternatives to lead-halide perovskites, in optoelectronics applications. Although iodide (I) and bromide (Br) mixing is a versatile tool for bandgap tuning in lead perovskites, similar mixed I/Br double perovskite films have not been reported in double perovskites, which may be due to the large activation energy for ion migration. In this work, mixed Br/I double perovskites were realized utilizing an anion exchange method starting from Cs 2 AgBiBr 6 solid thin-films with large grain-size. The optical and structural properties were studied experimentally and theoretically. Importantly, the halide exchange mechanism was investigated. Hydroiodic acid was the key factor to facilitate the halide exchange reaction, through a dissolution-recrystallization process. In addition, the common organic iodide salts could successfully perform halide-exchange while retaining high mixed-halide phase stability and strong light absorption capability., (© 2021 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

Head and neck squamous cell carcinoma (HNSCC) are the sixth most common cancer type in the world. Human papillomavirus (HPV) infection is an emerging risk factor for HNSCC. Immune infiltration of HNSCC is linked to therapeutic results. This article aimed to decide whether variations in HPV status affect immune infiltration, molecular mechanism, and how these results vary in HNSCC patients. We investigated the tumor-infiltrating immune cells (TIICs) and immune-related gene differences between HPV (+) and HPV (-) HNSCC. The gene expression quantification data of HNSCC and their clinical information were download from the TCGA database. Immune-related genes have been linked to the ImmPort platform. After analyzed of 22 TIICs in the HNSCC tumor environment by CIBERSORT and further assessment, lower memory B cell and higher T cell regulatory were connected with better HPV (-) HNSCC outcome, higher activated memory CD4 T cell, higher T cell regulatory, and lower activated NK cell were linked with better HPV (+) result. We finally got five forms of immune genes (CAMP, EDNRB, NTS, CXCL9, LHB) associated with HNSCC progression. Higher expressions of CAMP, EDNRB, and NTS were associated with increased overall survival in HPV (-) patients. Higher expression of CXCL9 and lower expression of LHB contributed to increased overall survival of HPV (+) patients. There tend to be discrepancies in the cell structure of TIICs and immune-related genes in HPV (-) and HPV (+) HNSCC. These variances are typically too crucial for the therapeutic outcome of the patient and the development of the tumor. In specific, our sample established these candidate immune cells and immune-related genes as candidate reservoirs for further researches., Competing Interests: None., (AJTR Copyright © 2021.)

Contrast-enhanced ultrasound (CEUS) offers the exciting prospect of retaining the ease of ultrasound imaging while enhancing imaging clarity, diagnostic specificity, and theranostic capability. To advance the capabilities of CEUS, the synthesis and understanding of new ultrasound contrast agents (UCAs) is a necessity. Many UCAs are nano- or micro-scale materials composed of a perfluorocarbon (PFC) and stabilizer that synergistically induce an ultrasound response that is both information-rich and easily differentiated from natural tissue. In this work, we probe the extent to which CEUS is modulated through variation in a PFC stabilized with fluorine-modified polydopamine nanoparticles (PDA NPs). The high level of synthetic tunability in this system allows us to study signal as a function of particle aggregation and PFC volatility in a systematic manner. Separation of aggregated and non-aggregated nanoparticles lead to a fundamentally different signal response, and for this system, PFC volatility has little effect on CEUS intensity despite a range of over 50 °C in boiling point. To further explore the imaging tunability and multimodality, Fe3+-chelation was employed to generate an enhanced photoacoustic (PA) signal in addition to the US signal. In vitro and in vivo results demonstrate that PFC-loaded PDA NPs show stronger PA signal than the non-PFC ones, indicating that the PA signal can be used for in situ differentiation between PFC-loading levels. In sum, these data evince the rich role synthetic chemistry can play in guiding new directions of development for UCAs.

Transvaginal ultrasound is widely used for ovarian cancer screening but has a high false positive rate. Photoacoustic imaging provides additional optical contrast to supplement ultrasound and might be able to improve the accuracy of screening. Here, we report two copper sulfide (CuS) nanoparticles types (nanodisks and triangular nanoprisms) as the photoacoustic contrast agents for imaging ovarian cancer. Both CuS nanoprisms and nanodisks were ~6 nm thick and ~26 nm wide and were coated with poly(ethylene glycol) to make them colloidally stable in phosphate buffered saline (PBS) for at least 2 weeks. The CuS nanodisks and nanoprisms revealed strong localized surface plasmon resonances with peak maxima at 1145 nm and 1098 nm, respectively. Both nanoparticles types had strong and stable photoacoustic intensity with detection limits below 120 pM. The circular CuS nanodisk remained in the circulation of nude mice (n=4) and xenograft 2008 ovarian tumors (n=4) 17.9-fold and 1.8-fold more than the triangular nanoprisms, respectively. Finally, the photoacoustic intensity of the tumors from the mice (n=3) treated with CuS nanodisks was 3.0-fold higher than the baseline. The tumors treated with nanodisks had a characteristic peak at 920 nm in the spectrum to potentially differentiate the tumor from adjacent tissues., Competing Interests: Conflicts of Interest The authors declare no competing financial interest

The personal ultraviolet (UV) dosimeter is a useful measurement tool to prevent UV induced dermal damages; however, conventional digital dosimeters are either bulky or require external power sources. Here, a wearable, colorimetric UV film dosimeter that provides color transition, from purple to transparent, is reported to indicate the UV dose. The film dosimeter is made of a purple photodegradable dye ((2Z,6Z)-2,6-bis(2-(2,6-diphenyl-4H-thiopyran-4-ylidene)ethylidene)cyclohexanone or DTEC) blended in low density polyethylene film. The DTEC film discolored 3.3 times more under the exposure of UV light (302 nm) than visible light (543 nm), and a UV bandpass filter is developed to increase this selectivity to UV light. The DTEC film completely discolors to transparency in 2 h under an AM 1.5 solar simulator, suggesting the potential as an indicator for individuals with types I-VI skin to predict interventions to avoid sunburn. Finally, the DTEC film is integrated with the UV bandpass filter on a wristband to function as a wearable dosimeter for low cost and convenient monitoring of sunlight exposure., Competing Interests: Conflict of Interest The authors declare no conflict of interest.

The interaction between methylene blue (MB) and sodium dodecyl sulfate (SDS) has been widely studied spectroscopically, but details about their interactions remain unclear. Here, we combined photoacoustic (PA) imaging with nanoparticle tracking analysis (NTA) and spectroscopy to further elucidate this interaction. PA imaging of 0.05 mM MB showed a 492-fold increase in intensity upon the addition of 3.47 mM SDS. Higher concentrations above SDS's critical micelle concentration (CMC) at 8.67 mM decreased the PA intensity by 54 times. Relative quantum yield measurements indicated that PA intensity increased as a result of fluorescence quenching. Meanwhile, NTA indicated an increased number of nonmicellar MB/SDS clusters at SDS concentrations below the CMC varying in size from 80 to 400 nm as well as a decreased number above the CMC. This trend suggested that MB/SDS clusters are responsible for the PA intensity enhancement. Comparison of PA intensities and spectral shifts with MB/hexadecyltrimethylammonium bromide, MB/sodium octyl sulfate, and MB/sodium chloride demonstrated that MB was bound to the sulfate moiety of SDS before and after micellization. Our observations suggest that MB forms aggregates with SDS at premicellar concentrations, and the MB aggregates disassociate as monomers that are bound to the sulfate moiety of SDS at micellar concentrations. These findings further clarify the process by which MB and SDS interact and demonstrate the potential for developing MB-/SDS-based contrast agents.

Photoacoustic imaging (PAI) is a non-invasive, high-resolution hybrid imaging modality that combines optical excitation and ultrasound detection. PAI can image endogenous chromophores (melanin, hemoglobin, etc.) and exogenous contrast agents in different medical applications. However, most current equipment uses sophisticated and complicated OPO lasers with tuning and stability features inconsistent with broad clinical deployment. As the number of applications of PAI in medicine increases, there is an urgent need to make the imaging equipment more compact, portable, and affordable. Here, portable light emitting diode - based photoacoustic imaging (PLED-PAI) was introduced and characterized in terms of system specifications, light source characterizations, photoacoustic spatial/temporal resolution, and penetration. The system uses two LED arrays attached to the sides of a conventional ultrasound transducer. The LED pulse repetition rate is tunable between 1 K Hz, 2 K Hz, 3 K Hz, and 4 K Hz. The axial resolution was 0.268 mm, and the lateral resolution was between 0.55 and 0.59 mm. The system could detect optical absorber (pencil lead) at a depth of 3.2 cm and the detection limits of indocyanine green (ICG) and methylene blue (MB) were 9 μM and 0.78 mM. In vivo imaging of labeled human mesenchymal stem cells was achieved to confirm compatibility with small animal imaging. The characterization we report here may have value to other groups evaluating commercially available photoacoustic imaging equipment.

We report a new approach to preparing phantoms using 3D printing. This device supports plastic tubing containing the contrast agent and is immersed in a solution with absorption or scattering properties that mimic tissue. Up to 12 tubing samples could be placed in the device with sample-to-sample spacing as low as 0.3 mm and at a constant distance from the transducer (±0.16 mm), which is critical in validating photoacoustic contrast agents. We also studied different types of tubing and found that tubing with a larger outside diameter has more inherent signal. Both 40% India Ink and lipids in the immersion media modulated the signal. Finally, we created a depth phantom and found that signal decayed following a linear relationship (R 2  = 0.997) with respect to distance from the focal point. We include computer-assisted drafting code the community can use to print this phantom or customized versions of this phantom.

Ultrasound is critical in many areas of medicine including obstetrics, oncology, and cardiology with emerging applications in regenerative medicine. However, one critical limitation of ultrasound is the low contrast of target tissue over background. Here, we describe a novel cup-shaped silica nanoparticle that is reminiscent of exosomes and that has significant ultrasound impedance mismatch for labelling stem cells for regenerative medicine imaging. These exosome-like silica nanoparticles (ELS) were created through emulsion templating and the silica precursors bis(triethoxysilyl)ethane (BTSE) and bis(3-trimethoxysilyl-propyl)amine (TSPA). We found that 40% TSPA resulted in the exosome like-morphology and a positive charge suitable for labelling mesenchymal stem cells. We then compared this novel structure to other silica structures used in ultrasound including Stober silica nanoparticles (SSN), MCM-41 mesoporous silica nanoparticles (MSN), and mesocellular foam silica nanoparticles (MCF) and found that the ELS offered enhanced stem cell signal due to its positive charge to facilitate cell uptake as well as inherently increased echogenicity. The in vivo detection limits were <500 cells with no detectable toxicity at the concentrations used for labelling. This novel structure may eventually find utility in applications beyond imaging requiring an exosome-like shape including drug delivery.