A framework of ecological security patterns in arid and semi-arid regions considering differences socioeconomic scenarios in ecological risk: Case of Loess Plateau, China.

Understanding the establishment of ecological security patterns in arid and semi-arid regions is critical for global ecological risk prevention, control, and sustainable development. Nonetheless, there remains a relative deficiency in ecological risk assessment and construction of Ecological Security Patterns (ESP) in these areas, along with insufficient verification regarding the changes in ecological security patterns under diverse scenarios. This study employs Morphological Spatial Pattern Analysis (MSPA) to identify ecological sources and utilizes circuit theory alongside Minimum Cumulative Resistance (MCR) to delineate ecological corridors.

Influences of climatic variation and human activities on vegetation photosynthesis dynamics in Southwest China.

Photosynthesis is a direct route for carbon sequestration in vegetation, and is influenced by climatic variation (CV) and human activities (HA). Therefore, a quantitative assessment of their influence on vegetation photosynthesis dynamics is pivotal for formulating effective carbon neutrality strategies. Herein, based on the solar-induced chlorophyll fluorescence index (SIF), which reflects the vegetation photosynthesis intensity, and TerraClimate meteorological data, we refined the residual trend approach by incorporating more climatic variables and their time effects on vegetation to assess the influences of CV and HA on SIF dynamics in Southwest China.

Synthesis, characterization and antifungal activity of imidazole chitosan derivatives.

Five novel imidazole-functionalized chitosan derivatives 3a-3e were synthesized via addition reactions of chitosan with imidazole derivatives. The partial incorporation of imidazole moiety in chitosan were confirmed by FTIR, UV, H NMR, XRD, SEM and GPC. Meanwhile, the antifungal activity against three common plant pathogenic fungi: Phytophthora nicotianae (P.

Synthesis and Antifungal Activities of Glucosamine Aromatic Derivatives Against Four Phytopathogenic Fungi of Crops.

A series of diversified glucosamine derivatives (3a-3y) was synthesized and their antifungal activity was examined against four kinds of phytopathogens, Fusarium graminearum (F. graminearum), Fusarium moniliforme (F. moniliforme), Curvularia.

Residents' future residential preference and its affecting factors in the rapid urbanization zone of rural China from a family life cycle perspective.

Understanding farmers' future residential preferences and the factors affecting these choices is crucial for tackling the issues related to hollow village management and rural planning. Despite limited research on the role of the family life cycle, this study explores how the family life cycle, characteristics of the household head, livelihood strategies, and resource availability shape farmers' future residential preferences. Data were collected from 777 households in China's main grain-producing area.

The rectangular tile classification model based on Sentinel integrated images enhances grassland mapping accuracy: A case study in Ordos, China.

Arid zone grassland is a crucial component of terrestrial ecosystems and plays a significant role in ecosystem protection and soil erosion prevention. However, accurately mapping grassland spatial information in arid zones presents a great challenge. The accuracy of remote sensing grassland mapping in arid zones is affected by spectral variability caused by the highly diverse landscapes.

Palladium-Catalyzed Domino Conversion of Aryl-Thianthreniums with Anhydrides: Rapidly Building Highly Functionalized Fluorenones.

As a class of rising electrophilic coupling reagents, aryl-thianthreniums (aryl-TTs) have been gaining immense attention. Herein, a novel palladium-catalyzed domino annulation of aryl-TTs with anhydrides is proposed to rapidly assemble a collection of highly functionalized fluorenones. This finding presents an innovative reaction pattern of aryl-TTs wherein the domino annulation version is first involved.

Quantifying the drought sensitivity of grassland under different climate zones in Northwest China.

Grassland is essential for maintaining the stability and functionality of terrestrial ecosystems. Although previous research has explored how grassland responds to drought, the drought sensitivity of grassland (DSG) across climate zones and aridity gradients remains uncertain. In this study, we conducted a comprehensive investigation spanning 1982 to 2015 in Northwest China.

Direct access to carbamates acylation of arylamines with dialkyl azodicarboxylates under metal-free conditions.

A novel C-N coupling of various arylamines with dialkyl azodicarboxylates under metal-free conditions for the rapid assembly of carbamates has been achieved. This established protocol features mild reaction conditions, simple operation, broad substrate scope, moderate to excellent yields and good tolerance of functional groups. Moreover, the potential synthetic utility of products was exemplified by a series of intriguing chemical operations.

Study on the quality and inkjet printing effect of the prepared washing-free disperse dye ink.

With the rapid development of digital inkjet printing, it will inevitably lead to the uneven quality of inkjet printing ink products on the market. Therefore, making a more comprehensive and accurate quality evaluation of digital printing ink is particularly important. In this study, a short process and environment-friendly washing-free disperse dye ink was prepared based on the research on ink quality.

Recent Advances in the Synthesis of 3,n-Fused Tricyclic Indole Skeletons via Palladium-Catalyzed Domino Reactions.

3,n-fused ( = 4-7) tricyclic indoles are pervasive motifs, embedded in a variety of biologically active molecules and natural products. Thus, numerous catalytic methods have been developed for the synthesis of these skeletons over the past few decades. In particular, palladium-catalyzed transformations have received much attention in recent years.

Design, Catalyst-Free Synthesis of New Novel α-Trifluoromethylated Tertiary Alcohols Bearing Coumarins as Potential Antifungal Agents.

A new method for the synthesis of α-trifluoromethylated tertiary alcohols bearing coumarins is described. The reaction of 3-(trifluoroacetyl)coumarin and pyrrole provided the target compounds with high yields under catalyst-free, mild conditions. The crystal structure of compound was investigated by X-ray diffraction analysis.

Rhodium(III)-catalyzed oxidative cross-coupling of benzoxazinones with styrenes C-H activation.

Vinylarenes represent an important class of core skeleton embedded in natural products, organic materials, and pharmaceutical molecules. Therefore, numerous efforts have been devoted to developing efficient methods for their preparation. Among them, transition-metal-catalyzed oxidative coupling of arenes and alkenes has proved to be a powerful method due to its high atom and step economy.

Spatio-Temporal Characteristics of Trade-Offs and Synergies in Ecosystem Services at Watershed and Landscape Scales: A Case Analysis of the Yellow River Basin (Henan Section).

The changes and interrelationships of ecosystem services at different global and regional scales have been actively investigated. Clarifying the trade-offs and synergies between ecosystem services from a multi-scale scientific perspective is vital to improve the coordinated and sustainable development of the watershed and ecological protection. As an important ecological barrier region of the Yellow River Basin, the Henan section provides a variety of important ecosystem services.

Highly Chemoselective Synthesis of Azaarene-Equipped CF-Tertiary Alcohols under Metal-Free Conditions and Their Fungicidal Activities.

A highly chemoselective reaction between α,β-unsaturated trifluoromethyl ketones with azaarenes under metal-free conditions was carried out, affording a range of valuable azaarene-equipped CF-tertiary alcohols in moderate to excellent yields (up to 95% yield) with good tolerance of functional groups, and their structures were confirmed by NMR, HRMS, and X-ray diffraction for validation. This method features simple reaction conditions (only solvent), high atom- and step-economy, and broad substrate scope. Moreover, most of the target products exhibited promising fungicidal activities, and compound exhibited 91.

Synthesis of Novel Indole Schiff Base Compounds and Their Antifungal Activities.

A series of novel indole Schiff base derivatives (-) containing a 1,3,4-thiadiazole scaffold modified with a thioether group were synthesized, and their structures were confirmed using FT-IR, H NMR, C NMR, and HR-MS. In addition, the antifungal activity of synthesized indole derivatives was investigated against (), (, (), ), and var. ( var.

Reversible Near-Infrared Fluorescent Probe for Rapid Sensing Sulfur Dioxide and Formaldehyde: Recognition and Photoactivation Mechanism and Applications in Bioimaging and Encryption Ink.

A novel near-infrared (NIR) fluorescent Probe was successfully developed for the reversible detection of sulfur dioxide derivatives and formaldehyde. The purple solution of Probe faded to colorless in 1.8 s with the addition of HSO.

Synthesis of spiropyrans the Rh(III)-catalyzed annulation of 3-aryl-2-benzo[][1,4]oxazines with diazo ketoesters.

Rh(III)-Catalyzed 1 : 2 coupling of 3-aryl-2-benzo[][1,4]oxazines with α-diazo-β-ketoesters has been realized for the mild synthesis of spiropyrans. The reaction proceeded twofold C-H activation followed by unusual [3+3] and [4+2] annulation with decent functional group tolerance. Moreover, a pyranoid-skeleton intermediate was isolated as a key intermediate as a result of monoalkylation and enol oxygen annulation, which offers direct mechanistic insight.

Carbon Storage Change Analysis and Emission Reduction Suggestions under Land Use Transition: A Case Study of Henan Province, China.

The significant spatial heterogeneity among river basin ecosystems makes it difficult for local governments to carry out comprehensive governance for different river basins in a special administrative region spanning multi-river basins. However, there are few studies on the construction of a comprehensive governance mechanism for multi-river basins at the provincial level. To fill this gap, this paper took Henan Province of China, which straddles four river basins, as the study region.

Hydroxylamines As Bifunctional Single-Nitrogen Sources for the Rapid Assembly of Diverse Tricyclic Indole Scaffolds.

Conventional approaches on using hydroxylamine derivatives as single nitrogen sources, for the construction of -membered ( > 3) N-heterocycles, rely upon two chemical operations by involving sequential nucleophilic and electrophilic C-N bond formations. Here, we report a highly efficient cascade of alkyne insertion/C-H activation/amination for the rapid preparation of a myriad of tricyclic indoles, in a single-step transformation, by using bifunctional secondary hydroxylamines. It is noteworthy that judicious selection of applicable amino agents, for enabling the prior oxidative addition of aryl iodide to initial Pd(0) species and subsequent two C-N bonds formation, was the key to the success of this reaction.

Do environmental conservation programs contribute to sustainable livelihoods? Evidence from China's grain-for-green program in northern Shaanxi province.

Several studies reported that conservation programs worldwide have profoundly reshaped participants' livelihoods and influenced other socio-economic processes. A fully understanding of how such conservation programs influence human lives is, therefore, crucial for their success. There, however, is little robust evidence of the effect of China's grain-for-green program (GGP), the largest conservation program in the world, on participants' livelihoods.

Factors affecting pesticide safety behaviour: The perceptions of Nepalese farmers and retailers.

Indiscriminate use of pesticides in vegetable farming is an emerging problem resulting in increasing health and environmental risks in developing countries including Nepal. As there are limited studies focusing on farmers' and retailers' knowledge related to pesticide use and associated risks as well as safety behaviour, this study assesses their perceptions of pesticide use, associated impacts on human and environmental health and safety behaviours. This study is also intended to quantify pesticide use in vegetable farming.

Rapid Assembly of Diversely Functionalized Spiroindenes by a Three-Component Palladium-Catalyzed C-H Amination/Phenol Dearomatization Domino Reaction.

A novel palladium-catalyzed three-component reaction of phenol-derived biaryls with N-benzoyloxyamines and norbornadiene (NBD) has been developed for the assembly of highly functionalized spiroindenes. This domino process was realized through NBD-assisted C-H amination and phenol dearomatization by forming one C-N bond and two C-C bonds in a single step. Preliminary studies indicated that asymmetric control of this transformation was feasible with chiral ligands.

Modular Assembly of Spirocarbocyclic Scaffolds through Pd -Catalyzed Intermolecular Dearomatizing [2+2+1] Annulation of Bromonaphthols with Aryl Iodides and Alkynes.

A novel palladium(0)-catalyzed dearomatizing [2+2+1] spiroannulation of 1-bromo-2-naphthols with aryl iodides and alkynes was developed for the rapid assembly of spiro[indene-1,1'-naphthalen]-2'-ones. This three-component cascade reaction was realized through consecutive Catellani-type C-H activation, unsymmetrical biaryl coupling, alkyne migratory insertion, and arene dearomatization. The potential utility of our method is illustrated by the one-step construction of the polycyclic skeletons of dalesconols A and B from alkyne-tethered aryl iodides and 1-bromo-2-naphthol.

Highly Stereoselective Synthesis of Imine-Containing Dibenzo[b,d]azepines by a Palladium(II)-Catalyzed [5+2] Oxidative Annulation of o-Arylanilines with Alkynes.

A novel palladium(II)-catalyzed [5+2] oxidative annulation of readily available o-arylanilines with alkynes has been developed for building a seven-membered N-heterocyclic architecture containing a biaryl linkage. This method is applicable to a wide range of unprotected o-arylanilines and internal alkynes, and results in the chemoselective preparation of imine-containing dibenzo[b,d]azepines in high yields with excellent diastereoselectivity with respect to the two types of stereogenic elements.