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1.
J Imaging Inform Med ; 2024 May 15.
Article in English | MEDLINE | ID: mdl-38750186

ABSTRACT

OBJECTIVES: To preoperatively predict the high expression of Ki67 and positive pituitary transcription factor 1 (PIT-1) simultaneously in pituitary adenoma (PA) using three different radiomics models. METHODS: A total of 247 patients with PA (training set: n = 198; test set: n = 49) were included in this retrospective study. The imaging features were extracted from preoperative contrast-enhanced T1WI (T1CE), T1-weighted imaging (T1WI), and T2-weighted imaging (T2WI). Feature selection was performed using Spearman's rank correlation coefficient and least absolute shrinkage and selection operator (LASSO). The classic machine learning (CML), deep learning (DL), and deep learning radiomics (DLR) models were constructed using logistic regression (LR), support vector machine (SVM), and multi-layer perceptron (MLP) algorithms. The area under the receiver operating characteristic (ROC) curve (AUC), sensitivity, specificity, accuracy, negative predictive value (NPV) and positive predictive value (PPV) were calculated for the training and test sets. In addition, combined with clinical characteristics, the best CML and the best DL models (SVM classifier), the DL radiomics nomogram (DLRN) was constructed to aid clinical decision-making. RESULTS: Seven CML features, 96 DL features, and 107 DLR features were selected to construct CML, DL and DLR models. Compared to CML and DL model, the DLR model had the best performance. The AUC, sensitivity, specificity, accuracy, NPV and PPV were 0.827, 0.792, 0.800, 0.796, 0.800 and 0.792 in the test set, respectively. CONCLUSIONS: Compared with CML and DL models, the DLR model shows the best performance in predicting the Ki67 and PIT-1 expression in PAs simultaneously.

2.
BMC Cancer ; 24(1): 521, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38658858

ABSTRACT

BACKGROUND: Emerging evidence suggests that the gut microbiota is associated with various intracranial neoplastic diseases. It has been observed that alterations in the gut microbiota are present in gliomas, meningiomas, and pituitary neuroendocrine tumors (Pit-NETs). However, the correlation between gut microbiota and craniopharyngioma (CP), a rare embryonic malformation tumor in the sellar region, has not been previously mentioned. Consequently, this study aimed to investigate the gut microbiota composition and metabolic patterns in CP patients, with the goal of identifying potential therapeutic approaches. METHODS: We enrolled 15 medication-free and non-operated patients with CP and 15 healthy controls (HCs), conducting sequential metagenomic and metabolomic analyses on fecal samples to investigate changes in the gut microbiota of CP patients. RESULTS: The composition of gut microbiota in patients with CP compared to HCs show significant discrepancies at both the genus and species levels. The CP group exhibits greater species diversity. And the metabolic patterns between the two groups vary markedly. CONCLUSIONS: The gut microbiota composition and metabolic patterns in patients with CP differ significantly from the healthy population, presenting potential new therapeutic opportunities.


Subject(s)
Craniopharyngioma , Feces , Gastrointestinal Microbiome , Pituitary Neoplasms , Humans , Craniopharyngioma/metabolism , Male , Female , Adult , Pituitary Neoplasms/metabolism , Pituitary Neoplasms/microbiology , Feces/microbiology , Middle Aged , Case-Control Studies , Young Adult , Adolescent , Metabolomics/methods , Metagenomics/methods , Metabolome
3.
Phytochemistry ; 222: 114108, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38663825

ABSTRACT

Twelve undescribed 2-(2-phenethyl)chromone dimers (1-12) were isolated from EtOAc extract of agarwood originating from Aquilaria filaria in the Philippines, guided by a UHPLC-MS analysis. Their structures were elucidated by 1D NMR, 2D NMR, and HR-ESI-MS spectra. The absolute configuration of 2-(2-phenylethyl)chromone dimers was determined by single-crystal X-ray diffraction analysis and comparison of the experimental and calculated ECD spectra. Compounds 1, 2, 5 and 9-12 exhibited potent to moderate anti-inflammatory activity with IC50 values in the range of 22.43 ± 0.86 to 53.88 ± 4.06 µM.


Subject(s)
Chromones , Thymelaeaceae , Wood , Thymelaeaceae/chemistry , Philippines , Chromones/chemistry , Chromones/isolation & purification , Chromones/pharmacology , Molecular Structure , Wood/chemistry , Animals , Structure-Activity Relationship , Mice , Dose-Response Relationship, Drug , Crystallography, X-Ray , Flavonoids
4.
Sci Total Environ ; 928: 172290, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38599391

ABSTRACT

The contamination of wetlands by heavy metals, exacerbated by agricultural activities, presents a threat to both organisms and humans. Heavy metals may undergo trophic transfer through the food web. However, the methods for quantifying the bioaccumulation and trophic transfer processes of heavy metals based on the food web remains unclear. In this study, we employed stable isotope technology to construct a quantitative oriental white stork's typical food web model under a more accurate scaled Δ15N framework. On this basis, the concentrations for heavy metal (Cu, Zn, Hg, Pb) were analyzed, we innovatively visualized the trophic transfer process of heavy metals across 13 nodes and 45 links and quantified the transfer flux based on the diet proportions and heavy metal concentrations of species, taking into account biomagnification effects and potential risks. Our findings revealed that as for Cu and Pb, the transfer flux level was consistent with diet proportion across most links. While Hg and Zn transfer flux level exceeded the corresponding diet proportion in the majority of links. In summary, Hg exhibited a significant biomagnification, whereas Cu, Zn, Pb experienced biodilution. The fish dietary health risk assessment for fish consumers showed that Hg, Pb posed certain risks. This research marks a significant step forward in the quantitative assessment of multi-link networks involving heavy metals within the food web.


Subject(s)
Bioaccumulation , Environmental Monitoring , Food Chain , Metals, Heavy , Water Pollutants, Chemical , Wetlands , Metals, Heavy/analysis , Metals, Heavy/metabolism , China , Water Pollutants, Chemical/metabolism , Water Pollutants, Chemical/analysis , Animals , Fresh Water , Fishes/metabolism
5.
ACS Nano ; 2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38314720

ABSTRACT

Solid-state Li metal batteries (SSLMBs) are widely investigated since they possess promising energy density and high safety. However, the poor interfacial compatibility between the electrolyte and electrodes limits their promising development. Herein, a robust composite electrolyte (poly(vinyl ethylene carbonate) electrolyte with 3 wt % of BaTiO3, PVEC-3BTO) with excellent interfacial performance is rationally designed by incorporating ferroelectric BaTiO3 (BTO) nanoparticles into the poly(vinyl ethylene carbonate) (PVEC) electrolyte matrix. Benefiting from the high dielectric constant and ferroelectric properties of BTO, the interfacial compatibility between electrolytes and electrodes was significantly improved. The enhanced Li+ transference number (0.64) of solid electrolyte and in situ generated BaF2 inorganic interphase contribute to the enhanced cycling stability of PVEC-3BTO based Li//Li symmetrical batteries. Furthermore, the antioxidation ability of PVEC-3BTO has also been enhanced by modulating the local electric field for good pairing with high-voltage LiCoO2 material. Therefore, in this work, the mechanism of BTO for improving interfacial compatibility is revealed, and also useful methods for addressing the interface issues of SSLMBs have been provided.

6.
J Neurosurg ; 140(1): 47-58, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-37382333

ABSTRACT

OBJECTIVE: Over the last decade, the extended endoscopic endonasal approach (EEEA) has evolved as a credible surgical alternative for removing craniopharyngiomas. However, postoperative cerebrospinal fluid (CSF) leak remains one of the most pressing concerns. Craniopharyngiomas often invade the third ventricle, resulting in a higher rate of third ventricle opening after surgery and potentially increasing the risk of postoperative CSF leak. Identifying the risk factors associated with CSF leak after EEEA for craniopharyngiomas may have more clinical value. Nevertheless, there is a lack of systematic studies on the topic. Previous studies yielded inconsistent results, probably due to heterogeneous pathologies or small sample sizes. Hence, the authors present the largest known single-institution case series of the use of purely EEEA for craniopharyngiomas to systematically study the risk factors for postoperative CSF leak. METHODS: The authors retrospectively reviewed 364 cases of adult patients with craniopharyngiomas who were treated at their institution from January 2019 to August 2022, and they analyzed the risk factors for postoperative CSF leak. RESULTS: The overall rate of postoperative CSF leak was 4.7%. In the univariate analysis, larger dural defect size (OR 8.293, 95% CI 3.711-18.534, p < 0.001) and lower preoperative serum albumin level (OR 0.812, 95% CI 0.710-0.928, p = 0.002) were associated with higher rates of postoperative CSF leak. Predominantly cystic tumors (OR 0.325, 95% CI 0.122-0.869, p = 0.025) were linked to decreased risk of postoperative CSF leak. However, postoperative lumbar drainage (OR 2.587, 95% CI 0.580-11.537, p = 0.213) and third ventricle opening (OR 1.718, 95% CI 0.548-5.384, p = 0.353) were not related to postoperative CSF leak. In the multivariate analysis, larger dural defect size (OR 8.545, 95% CI 3.684-19.821, p < 0.001) and lower preoperative serum albumin level (OR 0.787, 95% CI 0.673-0.919, p = 0.002) were identified as independent risk factors for postoperative CSF leak. CONCLUSIONS: The authors' repair technique yielded a reliable reconstructive outcome for high-flow CSF leak in EEEA for craniopharyngioma. Lower preoperative serum albumin level and larger dural defect size were identified as independent risk factors for postoperative CSF leak, potentially providing new insights into minimizing the risk of postoperative CSF leak. Third ventricle opening was not associated with postoperative CSF leak. Lumbar drainage may not be necessary for high-flow intraoperative leak, but this finding may require validation with a prospective randomized controlled trial in the future.


Subject(s)
Craniopharyngioma , Pituitary Neoplasms , Adult , Humans , Craniopharyngioma/surgery , Craniopharyngioma/complications , Retrospective Studies , Prospective Studies , Cerebrospinal Fluid Leak/epidemiology , Cerebrospinal Fluid Leak/etiology , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Risk Factors , Pituitary Neoplasms/surgery , Pituitary Neoplasms/complications , Multivariate Analysis , Serum Albumin , Skull Base/surgery
7.
J Clin Med ; 12(20)2023 Oct 16.
Article in English | MEDLINE | ID: mdl-37892690

ABSTRACT

OBJECTIVE: The enlarged endonasal approach (EEA) has emerged as the preferred surgical procedure for removing craniopharyngiomas, due to its advantages of direct visualization and reduction of blind corners. However, owing to a low incidence of papillary CPs (PCPs) compared to adamantinomatous CPs (ACPs), a full view of PCP based on the EEA approach is limited. In this paper, the authors present the largest series to date analyzing the clinical characteristics based on the EEA approach for PCPs. METHODS: A retrospective review was conducted on 101 PCPs patients who underwent endoscopic endonasal surgery (EEA) and whose condition was confirmed via postoperative pathology. The PCPs were classified into three types based on MRI data and intraoperative findings from EEA: suprasellar/intra-suprasellar (3V floor intact) type (Type I), suprasellar/intra-suprasellar (3V floor invasive) type (Type II), and intra-third ventricle type (Type III). The general characteristics of the three types of tumors were summarized, and postoperative follow-up was conducted to record detailed information on changes in vision, endocrine replacement, tumor recurrence, and quality of life. RESULTS: Out of the 101 cases, 36 (36.64%) were classified as type I, 52 (51.49%) as type II, and 13 (12.87%) as type III. The mean age of type III patients was 40.46 ± 14.15 years old, younger than the other two types (p = 0.021). Headache (84.62%) and memory decline (61.54%) were prominent features in patients with type III (p = 0.029). Visual impairment was more common in type II (80.77%, p = 0.01). Gross total resection (GTR) was achieved in 91 patients (90.10%). There were no significant differences in GTR rates among the three types of tumors. There were significant differences in quality of life among the three types of PCP (p = 0.004), and type III presented with the highest rate of good postoperative quality of life (92.31%) based on the KPS score. Thirteen (12.87%) tumors recurred within a mean follow-up time of 38 (range, 8-63) months. Type II PCPs (OR 5.826, 95%CI 1.185-28.652, p = 0.030) and relapsed patients (OR 4.485, 95%CI 1.229-16.374, p = 0.023) were confirmed as independent risk factors for tumor recurrence. CONCLUSIONS: Most of the PCPs including intra-third ventricle PCPs can be safely and effectively removed through neuroendoscopy with EEA. Suprasellar/intra-suprasellar (third cerebral ventricle floor-invasive) type PCPs may have a worse postoperative quality of life compared to the other two types, and it may be a strong predictor of tumor recurrence.

8.
Front Endocrinol (Lausanne) ; 14: 1167776, 2023.
Article in English | MEDLINE | ID: mdl-37854185

ABSTRACT

Objective: To investigate the clinical and pathological factors associated with preoperative hypothalamus invasion and postoperative outcomes of adamantinomatous craniopharyngiomas (ACPs) after the expanded endonasal approach (EEA) resection. Methods: Ninety-three specimens of ACPs, consisting of 71 primary and 22 recurrent tumors, were investigated for the expression of TGF-ß1, SMAD2, SMAD3, and ß-catenin by immunohistochemistry staining. The clinical information of relevant patients, including the extent of resection, hypothalamus invasion, endocrinopathy, complications, and prognosis, was reviewed. The relationships between the expression of these immunopathological markers and clinical factors were analyzed. Results: Endocrinological dysfunctions were more common in recurrent patients and primary patients with hypothalamus invasion in the comparisons. For recurrent patients, the rate of gross total resection (GTR) was significantly lower than for primary patients (63.6% vs. 90.1%, P = 0.007). According to radiological and intraoperative findings, invasive ACPs (IACPs) included 48 (67.6%) cases in primary tumors. The expression of TGF-ß1 and ß-catenin was significantly higher in recurrent tumors (P = 0.021 and P = 0.018, respectively) and IACPs (P = 0.008 and P = 0.004, respectively). The expression level of TGF-ß1 was associated with hypothalamus involvement (Puget grade, P = 0.05; Vile grade, P = 0.002), postoperative endocrinopathy (P = 0.01), and pituitary stalk preservation (P = 0.008) in primary patients. In addition, the extent of resection, treatment history, hypothalamic invasion, and level of TGF-ß1 expression had significant influences on tumor recurrence/progression after surgery separately. Conclusion: Our study demonstrated the potential role of TGF-ß1 in the regulation of hypothalamus invasion in ACPs and the prediction of prognosis after EEA surgery. The TGF-ß signaling pathway may represent a crucial mechanism in the aggressive behavior and progression of ACPs.


Subject(s)
Craniopharyngioma , Pituitary Neoplasms , Transforming Growth Factor beta1 , Humans , beta Catenin , Craniopharyngioma/metabolism , Craniopharyngioma/pathology , Craniopharyngioma/surgery , Neoplasm Recurrence, Local/pathology , Pituitary Neoplasms/metabolism , Pituitary Neoplasms/pathology , Pituitary Neoplasms/surgery , Signal Transduction , Transforming Growth Factor beta1/biosynthesis
9.
Biomolecules ; 13(7)2023 07 05.
Article in English | MEDLINE | ID: mdl-37509115

ABSTRACT

Craniopharyngioma (CP) is a benign tumor with a high rate of obesity and frequent recurrence. Moreover, the role of leptin/leptin receptors axis in obesity and the prognosis of CP is still unknown. Plasma leptin concentration and mRNA expression of leptin receptors were assessed in patients with CP. Moreover, the association between leptin/leptin receptors axis, weight-related outcomes, and progression-free survival (PFS) were explored in CP patients. Leptin receptors overexpressed in CP tumor tissue were compared to normal brain tissue (p < 0.05); compared to healthy controls, the concentration of leptin was elevated in CP with or without matched age, sex, and body mass index (BMI) (p < 0.05). The high plasma leptin level was an independent risk predictor for significant weight gain (adjusted odds ratio (aOR) = 2.29, and p = 0.030) and new-onset obesity (aOR = 6.64, and p = 0.016). High plasma leptin level (adjusted hazard ratio (aHR) = 3.74, and p = 0.011) and leptin receptor (LEPR) mRNA expression (aHR = 3.12, and p = 0.045) were independent risk factors for poor PFS in CP. Inappropriately elevated leptin relative to BMI and its failure to inhibit further weight gain indicate the existence of leptin resistance in patients with CP. Leptin and LEPR were independent predictors for PFS of patients with CP. The leptin/leptin receptors axis may be a potential therapeutic target for obesity in patients with CP.


Subject(s)
Craniopharyngioma , Pituitary Neoplasms , Humans , Leptin/genetics , Prospective Studies , Craniopharyngioma/genetics , Craniopharyngioma/complications , Receptors, Leptin/genetics , Clinical Relevance , Obesity , Weight Gain , Pituitary Neoplasms/genetics , RNA, Messenger/genetics
10.
Microb Biotechnol ; 16(6): 1333-1343, 2023 06.
Article in English | MEDLINE | ID: mdl-36946330

ABSTRACT

R-1,3-butanediol (R-1,3-BDO) is an important chiral intermediate of penem and carbapenem synthesis. Among the different synthesis methods to obtain pure enantiomer R-1,3-BDO, oxidation-reduction cascades catalysed by enzymes are promising strategies for its production. Dehydrogenases have been used for the reduction step, but the enantio-selectivity is not high enough for further organic synthesis efforts. Here, a short-chain carbonyl reductase (LnRCR) was evaluated for the reduction step and developed via protein engineering. After docking result analysis with the substrate 4-hydroxy-2-butanone (4H2B), residues were selected for virtual mutagenesis, their substrate-binding energies were compared, and four sites were selected for saturation mutagenesis. High-throughput screening helped identify a Ser154Lys mutant which increased the catalytic efficiency by 115% compared to the parent enzyme. Computer-aided simulations indicated that after single residue replacement, movements in two flexible areas (VTDPAF and SVGFANK) facilitated the volumetric compression of the 4H2B-binding pocket. The number of hydrogen bonds between the stabilized 4H2B-binding pocket of the mutant enzyme and substrate was higher (from four to six) than the wild-type enzyme, while the substrate-binding energy was decreased (from -17.0 kJ/mol to -29.1 kJ/mol). Consequently, the catalytic efficiency increased by approximately 115% and enantio-selectivity increased from 95% to 99%. Our findings indicate that compact and stable substrate-binding pockets are critical for enzyme catalysis. Lastly, the utilization of a microbe expressing the Ser154Lys mutant enzyme was proven to be a robust process to conduct the oxidation-reduction cascade at larger scales.


Subject(s)
Alcohol Oxidoreductases , Butylene Glycols , Catalysis , Butylene Glycols/metabolism , Alcohol Oxidoreductases/chemistry , Kinetics , Substrate Specificity
11.
Fitoterapia ; 165: 105422, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36592638

ABSTRACT

Four new 2-(2-phenethyl)chromone dimers (1-4) were isolated from EtOAc extract of agarwood originating from Aquilaria filaria from Philippines. Their structures were elucidated by spectroscopic analysis (1D and 2D NMR, and HRESIMS) and comparison of the experimental and computed ECD curves. Compounds 1-4 exhibited inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells with IC50 values in the range from 33.94 to 57.53 µM.


Subject(s)
Chromones , Thymelaeaceae , Chromones/pharmacology , Molecular Structure , Thymelaeaceae/chemistry , Magnetic Resonance Spectroscopy , Lipopolysaccharides , Flavonoids/chemistry
12.
Sensors (Basel) ; 24(1)2023 Dec 25.
Article in English | MEDLINE | ID: mdl-38202982

ABSTRACT

The functionalization of noble metals is an effective approach to lowering the sensing temperature and improving the sensitivity of metal oxide semiconductor (MOS)-based gas sensors. However, there is a dearth of comparative analyses regarding the differences in sensitization mechanisms between the two functionalization modes of noble metal loading and doping. In this investigation, we synthesized Pt-doped CuO gas-sensing materials using a one-pot hydrothermal method. And for Pt-loaded CuO, Pt was deposited on the synthesized pristine CuO surface by using a dipping method. We found that both functionalization methods can considerably enhance the response and selectivity of CuO toward NO2 at low temperatures. However, we observed that CuO with Pt loading had superior sensing performance at 25 °C, while CuO with Pt doping showed more substantial response changes with an increase in the operating temperature. This is mainly due to the different dominant roles of electron sensitization and chemical sensitization resulting from the different forms of Pt present in different functionalization modes. For Pt doping, electron sensitization is stronger, and for Pt loading, chemical sensitization is stronger. The results of this study present innovative ideas for understanding the optimization of noble metal functionalization for the gas-sensing performance of metal oxide semiconductors.

13.
Heliyon ; 8(12): e11822, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36478839

ABSTRACT

Space-time adaptive focusing is the most prominent feature of time-reversal electromagnetic waves. This paper studies the spatial power synthesis technology of distributed motion platforms based on time-reversal electromagnetic waves. Firstly, the spatial power synthesis process based on time-reversal on a distributed fixed platform is modeled. Then, the time-reversal signal processing process of a distributed array on the motion platform is deduced, and the feasibility of realizing precise power focusing is verified in theory. Finally, the factors affecting the power synthesis effect in the target area are analyzed. The simulation results indicate that the spatial power synthesis on the distributed motion platform based on the time-reversal can effectively balance between power focusing effect and computational complexity. Also, the proposed method has better efficiency than the existing techniques, and it has strong practicability and feasibility.

14.
Sensors (Basel) ; 22(10)2022 May 12.
Article in English | MEDLINE | ID: mdl-35632095

ABSTRACT

Adversarial examples have aroused great attention during the past years owing to their threat to the deep neural networks (DNNs). Recently, they have been successfully extended to video models. Compared with image cases, the sparse adversarial perturbations in the videos can not only reduce the computation complexity, but also guarantee the crypticity of adversarial examples. In this paper, we propose an efficient attack to generate adversarial video perturbations with large sparsity in both the temporal (inter-frames) and spatial (intra-frames) domains. Specifically, we select the key frames and key pixels according to the gradient feedback of the target models by computing the forward derivative, and then add the perturbations on them. To overcome the problem of dimensional explosion in the video, we introduce super-pixels to decrease the number of pixels that need to compute gradients. The proposed method is finally verified under both the white-box and black-box settings. We estimate the gradients using natural evolution strategy (NES) in the black-box attacks. The experiments are conducted on two widely used datasets: UCF101 and HMDB51 versus two mainstream models: C3D and LRCN. Results show that compared with the state-of-the-art method, our method can achieve the similar attacking performance, but it pollutes only <1% pixels and costs less time to finish the attacks.


Subject(s)
Neural Networks, Computer
15.
Entropy (Basel) ; 24(3)2022 Mar 12.
Article in English | MEDLINE | ID: mdl-35327907

ABSTRACT

Deep neural networks in the area of information security are facing a severe threat from adversarial examples (AEs). Existing methods of AE generation use two optimization models: (1) taking the successful attack as the objective function and limiting perturbations as the constraint; (2) taking the minimum of adversarial perturbations as the target and the successful attack as the constraint. These all involve two fundamental problems of AEs: the minimum boundary of constructing the AEs and whether that boundary is reachable. The reachability means whether the AEs of successful attack models exist equal to that boundary. Previous optimization models have no complete answer to the problems. Therefore, in this paper, for the first problem, we propose the definition of the minimum AEs and give the theoretical lower bound of the amplitude of the minimum AEs. For the second problem, we prove that solving the generation of the minimum AEs is an NPC problem, and then based on its computational inaccessibility, we establish a new third optimization model. This model is general and can adapt to any constraint. To verify the model, we devise two specific methods for generating controllable AEs under the widely used distance evaluation standard of adversarial perturbations, namely Lp constraint and SSIM constraint (structural similarity). This model limits the amplitude of the AEs, reduces the solution space's search cost, and is further improved in efficiency. In theory, those AEs generated by the new model which are closer to the actual minimum adversarial boundary overcome the blindness of the adversarial amplitude setting of the existing methods and further improve the attack success rate. In addition, this model can generate accurate AEs with controllable amplitude under different constraints, which is suitable for different application scenarios. In addition, through extensive experiments, they demonstrate a better attack ability under the same constraints as other baseline attacks. For all the datasets we test in the experiment, compared with other baseline methods, the attack success rate of our method is improved by approximately 10%.

16.
J Environ Manage ; 308: 114593, 2022 Apr 15.
Article in English | MEDLINE | ID: mdl-35121461

ABSTRACT

Protected areas (PAs) have been established worldwide to conserve biodiversity. However, the conservation effectiveness of different PA functional zones remains poorly understood. Here, we investigated National Nature Reserves (NNRs) in China to explore and quantify the conservation in their core, buffer, and experimental zones. We compared the area and proportion of forest loss for these functional zones during the period from 2001 to 2018. The results showed that the forest loss in NNRs showed a decreasing trend since 2011, indicating that NNRs reduced the forest loss. There was no significant difference of forest loss proportion (p = 0.42) between the core zones (0.60 ± 1.32%) and buffer zones (0.55 ± 0.88%), implying that their performance in forest conservation was similar. There was a significant difference between experimental and core zones as well as between experimental and buffer zones both in forest loss area and proportion (p ˂ 0.05). We confirmed that the proportion of functional zones significantly affects the conservation effectiveness, i.e., an improper proportion of core zones or buffer zones may lead to forest loss. Therefore, we suggest an optimal proportion of core and buffer zones at 30%-50% and 10%-40%, respectively. Overall, the effectiveness of functional zones in forest nature reserves was assessed on a national scale. The results of this study support the recent adjustment in the PA functional zoning system in China.


Subject(s)
Conservation of Natural Resources , Ecosystem , Biodiversity , China , Conservation of Natural Resources/methods , Forests
17.
Conserv Biol ; 36(4): e13887, 2022 08.
Article in English | MEDLINE | ID: mdl-34989447

ABSTRACT

Previous assessments of the effectiveness of protected areas (PAs) focused primarily on changes in human pressure over time and did not consider the different human-pressure baselines of PAs, thereby potentially over- or underestimating PA effectiveness. We developed a framework that considers both human-pressure baseline and change in human pressure over time and assessed the effectiveness of 338 PAs in China from 2010 to 2020. The initial state of human pressure on PAs was taken as the baseline, and changes in human pressure index (HPI) were further analyzed under different baselines. We used the random forest models to identify the management measures that most improved effectiveness in resisting human pressure for the PAs with different baselines. Finally, the relationships between the changes in the HPI and the changes in natural ecosystems in PAs were analyzed with different baselines. Of PAs with low HPI baselines, medium HPI baselines, and high HPI baselines, 76.92% (n=150), 11.11% (n=12), and 22.86% (n=8) , respectively, showed positive effects in resisting human pressure. Overall, ignoring human-pressure baselines somewhat underestimated the positive effects of PAs, especially for those with low initial human pressure. For PAs with different initial human pressures, different management measures should be taken to improve effectiveness and reduce threats to natural ecosystems. We believe our framework is useful for assessing the effectiveness of PAs globally, and we recommend it be included in the Convention on Biological Diversity Post-2020 Strategy.


Las evaluaciones previas de la efectividad de las áreas protegidas (AP) se han enfocado principalmente en los cambios de las presiones humanas con el tiempo y no han considerado las diferentes líneas base de las presiones humanas en las AP, por lo que potencialmente han sobrestimado o subestimado su efectividad. Desarrollamos un marco de trabajo que considera las líneas base de presión humana y los cambios de las presiones humanas con el tiempo y evaluamos a la efectividad de 338 AP en China entre 2010 y 2020. Consideramos el estado inicial de la presión humana en las AP como la línea base y analizamos los cambios en el índice de presión humana (IPH) bajo diferentes líneas base. Utilizamos modelos de bosque aleatorio para identificar las medidas de gestión que más aumentaron la efectividad de la resistencia a las presiones humanas en las AP con líneas base diferentes. Finalmente, analizamos con diferentes líneas base las relaciones entre los cambios en el IPH y los cambios en los ecosistemas naturales de las AP. De las AP con líneas base de IPH bajas, medianas y altas, 76.92% (n=150), 11.11% (n=12) y 22.86% (n=8), respectivamente, mostraron efectos positivos de resistencia a las presiones humanas. En general, si ignoramos las líneas base de las presiones humanas, se subestiman los efectos positivos de las AP de una u otra manera, especialmente aquellas con poca presión humana al inicio. En el caso de las AP que al inicio tienen diferentes presiones humanas, se deben tomar diferentes medidas de gestión para mejorar la efectividad y reducir las amenazas a los ecosistemas naturales. Creemos que nuestro marco de trabajo sirve para evaluar la efectividad mundial de las AP y recomendamos que se incluya en la Estrategia Post-2020 de la Convención sobre la Diversidad Biológica. Mejoría de la Efectividad de un Área Protegida al Considerar Diferentes Líneas Base de Presión Humana.


Subject(s)
Conservation of Natural Resources , Ecosystem , Biodiversity , China , Humans
18.
Sci Total Environ ; 764: 142895, 2021 Apr 10.
Article in English | MEDLINE | ID: mdl-33131857

ABSTRACT

Protected areas (PAs) are considered essential for biodiversity conservation, and concerns about the effectiveness of PAs in terms of reducing deforestation are growing. However, few studies have identified the management measures that best reduce deforestation within existing PAs. Here, we carried out 10-year (from 2007 to 2016) field surveys and obtained a database of 10 management measures of 227 PAs mainly protecting forest ecosystems in China. We examined the contributions of the above 10 management measures in relation to the effectiveness of 227 PAs in reducing deforestation. Our results indicated that 52.68% of PAs had positive effects related to reducing deforestation (E > 0, P < 0.05), while 16.52% of PAs had negative effects (E < 0, P < 0.05). The most important management measures affecting the effectiveness of PAs in reducing deforestation were funding, infrastructure, and scientific research and monitoring. Thus, our study provides evidence indicating that improved funding and scientific research benefit the effectiveness of PAs. The findings have global implications for guiding PAs to take explicit measures to improve the outcomes of biodiversity conservation.


Subject(s)
Ecosystem , Forestry , Biodiversity , China , Conservation of Natural Resources , Forests
19.
Environ Sci Ecotechnol ; 2: 100025, 2020 Apr.
Article in English | MEDLINE | ID: mdl-36160928

ABSTRACT

Biodiversity conservation plays an important role in the sustainable development of human society. China had made significant progress in biodiversity conservation studies and practices. This paper reviews major achievements in China in the past decades, especially those since 2010. In terms of the science behind biodiversity conservation, Chinese scholars have made significant contributions to priority research subjects, including mechanisms for maintaining biological communities and the relationship between biodiversity and ecosystem functioning. Simultaneously, biodiversity conservation and management systems specific to China have been basically established. The Chinese Government and researchers have undertaken a number of investigations, scientific studies, and monitoring, and have established relevant databases. With efforts taken to protect and restore biodiversity and ecosystems, the concept of biodiversity has gradually become popular in China. This review is an attempt to share with the world the learning from China's progress towards becoming an ecological civilization and highlights that the efforts towards biodiversity conservation need to be organically integrated with sustainable development goals.

20.
PLoS One ; 9(4): e95081, 2014.
Article in English | MEDLINE | ID: mdl-24743693

ABSTRACT

Anthropogenic landscape alteration is rather common in many protected areas (PAs), jeopardizing the efficacy of PAs conservation. However, the general consensus is that PAs still remain effective in habitat conservation. To assess the efficacy of landscape-level conservation, we examined landscape alterations in the Changbai Mountain Biosphere Reserve (CMBR), which was established in 1960 as a "flagship" protected area in China. Based on analyses of high-resolution satellite images and data of forest inventory, field survey and interview, we developed two new indexes to assess the efficacy of landscape conservation, i.e. the quality index of protected landscape and the interference index of anthropogenic landscape. From 1993 to 2012, the quality index increased from 74.48 to 75.50, and the interference index decreased from 0.49 to 0.06, suggesting that the overall quality of protected landscape improved and the degree of anthropogenic interference decreased in CMBR. The increase in landscape quality was mainly due to the progressive vegetation recovery of previous cutover land in the windthrow area, the cease of the use of the cultivated land, and the amelioration of spatial pattern of protected landscape. We conclude that the current landscape conservation methods used in CMBR are effective, and the method we developed has the potential to be used to assess the efficacy of landscape-level conservation in nature reserves worldwide.


Subject(s)
Conservation of Natural Resources/methods , Ecosystem , China
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