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Anisotropy plays a unique role in the structural regulation of metal-organic frameworks (MOFs) and their composites, especially at the micro- and nanoscale. However, there is a lack of a understanding of MOF micro/nanoparticles (MNPs) from the perspective of morphological anisotropy. In this Minireview, recent advances in anisotropic MOF MNPs are summarized, with a focus on how morphological anisotropy leads to innovative structures and modulates properties. First, anisotropic pristine MOF MNPs with diverse morphologies are introduced and classified by their morphology-dependent and morphology-independent anisotropy. Secondly, the anisotropy-enabled site-selective higher-order construction of MOF-based materials is highlighted. Finally, challenges and prospects for anisotropic MOFs are discussed, aiming to provide inspiration for further developments in this interesting research field.

Silverleaf whitefly (SLW), Bemisia argentifolii Bellows and Perring, is one of the most noxious pests of numerous field and vegetable crops, causing billions of dollars worth of damage throughout the world. SLW is a phloem feeder whose feeding is likely to interfere with phloem transport. The aim of this study was to test the hypothesis that SLW infestation impairs carbohydrate export from source leaves, and consequently increases their carbohydrate content. The youngest fully expanded leaves of cotton (Gossypium hirsutum L., cv. Siv'on), grown under SLW-infested and noninfested conditions, were characterized for their diurnal changes in carbohydrate content and photoassimilate export. SLW infestation induced a considerable reduction in net photosynthetic rate (P n ), coupled with increased sucrose, glucose and fructose and decreased starch concentrations. Export rate was determined after 14 CO 2 pulse-labeling both by in situ monitoring of leaf radioactivity and by analyzing the content and radioactivity of the major carbon metabolites. Radioactive counting indicated a lower rate of 14 C efflux for the infested plants. A similar trend was found for the specific activities of sucrose and the three soluble sugars combined (sucrose, glucose and fructose). A single exponential decay function with asymptote was fitted to the above efflux curves. All the calculated exponential coefficients demonstrated lower export rates after SLW injury. These results indicate that SLW impairs photoassimilate export, suggesting possible down-regulation of P n due to increased foliar soluble sugar contents.

The silverleaf whitefly (SLW), Bemisia argentifolii (Bellows and Perring), has been a severe pest of numerous field and vegetable crops for many years. Nevertheless, little has been reported on the complex interactions between SLW and its host plants. This study was aimed at investigating the effects of SLW on cotton (Gossypium hirsutum L.) photosynthesis and productivity under various irrigation and N fertilization regimes. Cotton plants (cv. Siv'on) were examined during an entire growing season in two factorial-designed screenhouse experiments consisting of two irrigation regimes (I) × two N application rates × two SLW levels (noninfested vs. infested). Buildup of the SLW population was markedly higher on N-fertilized plants than on N-deficient plants. Seed cotton yield was reduced by SLW infestation under all combinations of I × N treatments by about 40%. Yield reduction (noninfested minus infested) was significantly correlated with the number of SLW adults on the maximally infested leaf at peak flowering (r 2 = 0.94, P < 0.05 in 1995; r 2 = 0.91, P < 0.05 in 1996). Photosynthetic rate decreased 50% at about 60 d after SLW introduction. The relative photosynthetic rate (infested/noninfested) was significantly correlated with SLW adult density on the maximally infested leaf (r 2 = 0.72, P < 0.001 in 1995; r 2 = 0.53, P < 0.01 in 1996). The reduced photosynthetic rate was associated with reductions in chlorophyll variable fluorescence (Fv/Fm) and fluorescence yield. No substantial changes were found in stomatal conductance, intercellular CO 2 concentration, and leaf chlorophyll content. These findings indicate that SLW infestation impairs, either directly or indirectly, the photochemical reaction of the photosynthetic system in cotton plants.

Reduced plant productivity induced by silverleaf whitefly (SLW), Bemisia argentifolii Bellows and Perring, is often associated with reduced net photosynthetic rate (P n ). This study was aimed at characterizing the effects of SLW on photosynthetic activity in cotton and the underlying mechanisms. Cotton (Gossypium hirsutum L. cv. Siv'on) plants were examined under SLW-infested and non-infested conditions and subjected to measurements of gas exchange, chlorophyll content and chlorophyll fluorescence. SLW infestation significantly reduced the P n of cotton by 22-54% throughout the day as well as throughout most of the examined ranges of photosynthetic photon flux density (PPFD) and CO 2 concentrations. Stomatal conductance was also reduced by SLW injury, while intercellular CO 2 concentration (C i ) was not affected, suggesting that stomatal limitation is not the major factor limiting P n . This conclusion was further supported by estimates of stomatal limitation, based on P n /C i curves, which were not affected by SLW infestation. On the other hand, non-stomatal limitation induced by SLW was over 2-fold higher than stomatal limitation. Chlorophyll a and b contents were not modified by SLW infestation. Fluorescence ratio (F v /F m ) and the effective quantum yield of PSII were reduced by less than 10%; thus, impaired photochemical reaction is probably not the only factor limiting P n under SLW infestation. In conclusion, SLW-induced P n reduction in cotton was due to non-stomatal factors, possibly induced by impaired carbon fixation and/or carbohydrate export.

By the addition of equivalent amount of appropriate amine on the carbon-carbon double bond of N-substituted maleamic acids under the influence of pyridine, a number of potential hypocholesteremics, N,N2-disubstituted DL-β-asparagines was prepared. For all N-alkyl- and N-arylmaleamic acids, the addition proceeded smoothly and resulted in satisfactory yields, but in the cases of N-heterocyclic analogs, transamidation was observed to occur simultaneously with the addition reactions.

In a search for substances that might be useful hypocholesteremic agents, a series of twenty five N-substituted maleamic acids was prepared. These compounds were produced in satisfactory yields by the aminolysis of maleic anhydride with appropriate aliphatic, aromatic and heterocyclic amines in various solvents under similar conditions. Analytical data as well as spectroscopic characterizations are provided.