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Chlorophyll plays a critical role in assessing the photosynthetic capacity and health of grasslands. However, existing studies on the hyperspectral inversion of chlorophyll have mainly focused on field crops, leading to limited accuracy when applied to natural grasslands due to their complex canopy structures and species diversity. This study aims to address this challenge by extrapolating the measured leaf chlorophyll to the canopy level using the green vegetation coverage approach. Additionally, fractional-order derivative (FOD) methods are employed to enhance the sensitivity of hyperspectral data to chlorophyll. Several FOD spectral indices are developed to minimize interference from factors such as bare soil and hay, resulting in improved chlorophyll estimation accuracy. The study utilizes partial least squares regression (PLSR) and support vector machine regression (SVR) to construct inversion models based on full-band FOD, two-band FOD spectral indices, and their combination. Through comparative analysis, the optimal model for estimating grassland chlorophyll content is determined, yielding an R2 value of 0.808, RMSE value of 1.720, and RPD value of 2.347. [ABSTRACT FROM AUTHOR]

Simple, rapid and sensitive and synchronous fluorescence spectrometry (SFS) were developed for determination the fluoroquinolones of ciprofloxacin (CIP), norfloxacin (NOR) and enrofloxacin (ENR) separately in water solutions and in medicinal preparations. The optimized wavelength intervals between the emission and excitation wavelengths were 170 nm, 160 nm and 170 nm for CIP, NOR and ENR, respectively. The different experimental parameters affecting the synchronous fluorescence intensities of the three fluoroquinolones were carefully studied. Under the optimal conditions, good linearity was obtained over the range of 0.01 to 1.20 mg/L, 0.005 to 0.45 mg/L and 0.005 to 0.60 mg/L for the CIP, NOR and ENR, and with good relative standard deviations below 1.9% (n=9). In addition, the detection limits for CIP, NOR and ENR were 0.17 μg/L, 0.013 μg/L and 0.055 μg/L, respectively. What is more, compared with the conventional fluorescence spectrometry, the SFS could detect lower concentrations of each fluoroquinolone. Moreover, the proposed SFS were validated and successfully applied for the quantitative assay of each fluoroquinolone in medicinal preparations.

The aim of this paper is to analyse the Romanian tourism market. We included key updates in current years. We presented a SWOT analysis of Romanian tourism and a tourism forecast. The outlook for Romania's tourism industry is broadly positive, with slow but steady growth expected across our key market indicators for the duration of our forecast period (2018-2022). International visitor numbers are set to rise over the medium term.

This study describes the preparation and properties of a novel aliphatic cost-effective segmented polyurethanes (SPUs) based on poly(ether ester) (poly-(ε-caprolactone-co-l-lactide)-poly(ethylene glycol)-poly-(ε-caprolactone-co-l-lactide), PECLA) and uniform-size diurethane diisocyanates (HDI-BDO-HDI). PECLA was synthesized via bulk ring-opening polymerization with poly(ethylene glycol) (PEG) as an initiator andε-caprolactone,l-lactide as monomers. By chain extension of PECLA diol with HDI-BDO-HDI, three SPUs with different hydrophilic segments content and hard segments content were obtained. The chemical structures of the chain extender, PECLA and SPUs were confirmed by1H NMR,13C NMR, FT-IR, HR-TOF-MS and GPC. The influences of PEG content and uniform-size hard segments onin vitrodegradability and mechanical properties of SPU films were researched. Similar thermostability observed in TGA curves of SPU films indicated that the hard segments and PEG content had little influence on the thermostability. The formation of microsphase-separated morphologies, which were demonstrated by the results of DSC and XRD, and physical-linking (H-bonds) network structures led to better mechanical properties of SPU films (ultimate stress: 23.1–17.9 MPa; elongation at break: 840–1130%). The results of water absorption and water contact angle showed that the bulk and surface hydrophilicity were closely related with the hydrophilic PEG content in SPU backbone. And the water absorption being less than 10 wt% indicated that the SPU films had low swelling property.In vitrohydrolytic degradation studies showed that the time of the SPU films becoming fragments was 34–19 days and the degradation rate increased with the increasing content of hydrophilic segments in SPUs, indicating that the degradation rate of SPU films could be controlled by adjusting PEG content. Cytotoxicity test of film extracts were conducted using L929 cells, and the relative growth rate exceeded 90% after incubation for 24, 48 and 72 h, showing excellent cytocompatibility. The acceptable mechanical properties, controllable biodegradability and excellent cytocompatibility of the polyurethanes can make them good candidates for further biomedical applications. [ABSTRACT FROM AUTHOR]

To accurately locate human eye features, such as eye contours, iris boundaries and the coordinates of pupil centers and canthi, a hierarchical approach was proposed. First, an AdaBoost based eye detector was trained for extracting the sub-images containing eyes areas, and the sub-images were enhanced by single-scale Retinex algorithm. Second, the pupil centers and iris boundaries were located by gradient Hough circle transform in the sub-images. Third, the eyes areas were segmented by FCM clustering for constructing the initial signed distance function which was the Level Set function of C-V Model. Finally, the eye contours and canthi were located using C-V Model. With the combination of FCM clustering and C-V Model, the convergent speed of C-V Model was increased by 64.1% on the Purdue AR face test set, while the locating accuracy was increased by 8.3%. This approach is immune to complicated background and illumination changes, showing its high robustness. Results prove the efficiency of this approach. [ABSTRACT FROM AUTHOR]

The booming development of nanomedicine offers great opportunities for cancer diagnostics and therapeutics. Herein, a magnetic targeting-enhanced cancer theranostic strategy using a multifunctional magnetic-plasmonic nano-agent is developed, and a highly effective in vivo tumor photothermal therapy, which is carefully planed based on magnetic resonance (MR)/photoacoustic (PA) multimodal imaging, is realized. By applying an external magnetic field (MF) focused on the targeted tumor, a magnetic targeting mediated enhanced permeability and retention (MT-EPR) effect is observed. While MR scanning provides tumor localization and reveals time-dependent tumor homing of nanoparticles for therapeutic planning, photoacoustic imaging with higher spatial resolution allows noninvasive fine tumor margin delineation and vivid visualization of three dimensional distributions of theranostic nanoparticles inside the tumor. Utilizing the near-infrared (NIR) plasmonic absorbance of those nanoparticles, selective photothermal tumor ablation, whose efficacy is predicted by real-time infrared thermal imaging intra-therapeutically, is carried out and then monitored by MR imaging for post-treatment prognosis. Overall, this study illustrates the concept of imaging-guided MF-targeted photothermal therapy based on a multifunctional nano-agent, aiming at optimizing therapeutic planning to achieve the most efficient cancer therapy. [ABSTRACT FROM AUTHOR]

Recently, near-infrared (NIR) absorbing conjugated polymeric nanoparticles have received significant attention in photothermal therapy of cancer. Herein, polypyrrole (PPy), a NIR-absorbing conjugate polymer, is used to coat ultra-small iron oxide nanoparticles (IONPs), obtaining multifunctional IONP@PPy nanocomposite which is further modified by the biocompatible polyethylene glycol (PEG) through a layer-by-layer method to acquire high stability in physiological solutions. Utilizing the optical and magnetic properties of the yielded IONP@PPy-PEG nanoparticles, in vivo magnetic resonance (MR) and photoacoustic imaging of tumor-bearing mice are conducted, revealing strong tumor uptake of those nanoparticles after intravenous injection. In vivo photothermal therapy is then designed and carried out, achieving excellent tumor ablation therapeutic effect in mice experiments. These results promise the use of multifunctional NIR-absorbing organic-inorganic hybrid nanomaterials, such as IONP@PPy-PEG presented here, for potential applications in cancer theranostics. [ABSTRACT FROM AUTHOR]

Background: The aggressiveness of prostate cancer (PCa) is crucial in determining treatment method. The purpose of this study was to establish a 2.5-dimensional (2.5D) deep transfer learning (DTL) detection model for the automatic detection of clinically significant PCa (csPCa) based on bi-parametric magnetic resonance imaging (bp-MRI)., Methods: A total of 231 patients, including 181 with csPCa and 50 with non-clinically significant PCa (non-csPCa), were enrolled. Stratified random sampling was then employed to divide all participants into a training set [185] and a test set [46]. The DTL model was obtained through image acquisition, image segmentation, and model construction. Finally, the diagnostic performance of the 2.5D and 2-dimensional (2D) models in predicting the aggressiveness of PCa was evaluated and compared using receiver operating characteristic (ROC) curves., Results: DTL models based on 2D and 2.5D segmentation were established and validated to assess the aggressiveness of PCa. The results demonstrated that the diagnostic efficiency of the DTL model based on 2.5D was superior to that of the 2D model, regardless of whether in a single or combined sequence. Particularly, the 2.5D combined model outperformed other models in differentiating csPCa from non-csPCa. The area under the curve (AUC) values for the 2.5D combined model in the training and test sets were 0.960 and 0.949, respectively. Furthermore, the T2-weighted imaging (T2WI) model showed superiority over the apparent diffusion coefficient (ADC) model, but was not as effective as the combined model, whether based on 2.5D or 2D., Conclusions: A DTL model based on 2.5D segmentation was developed to automatically evaluate PCa aggressiveness on bp-MRI, improving the diagnostic performance of the 2D model. The results indicated that the continuous information between adjacent layers can enhance the detection rate of lesions and reduce the misjudgment rate based on the DTL model., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-24-587/coif). N.D. reports that this research was supported by the Suzhou Science and Technology Development Plan (grant No. SKYD2023240) and Suzhou Wujiang District Health Commission “Promoting Health through Science and Education” Project (grant No. WWK202110). S.Y. reports that this research was supported by the Suzhou City “Promoting Health through Science and Education” Youth Science and Technology Project (grant No. KJXW2022077). The other authors have no conflicts of interest to declare., (2024 Quantitative Imaging in Medicine and Surgery. All rights reserved.)