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Background Immunotherapy has become increasingly important in the treatment of various malignant tumors. The interaction between tumor cells and the tumor microenvironment (TME) plays a crucial role in the efficacy of immunotherapy. The phenotype of cancer cells is thought to be influenced by lysosomal activity. The overall activity of lysosomes, including autophagy, has been shown to inhibit tumor occurrence. Nonetheless, the relationship between lysosomal function in Colon Adenocarcinoma (COAD) and clinical prognosis, immune cell infiltration, and response to immunotherapy remain to be elucidated. Methods We thoroughly determined the relationship between lysosomes and transcription patterns, prognosis, and immune cell infiltration by carefully evaluating 32 lysosomal-related genes (LRGs). Subsequently, we evaluated their value in COAD treatment outcomes and prognosis prediction. Results We explored the genetic changes of LRGs in COAD samples and discovered their expression patterns using the TCGA and GEO databases. We identified two relevant subgroups as well as Established that clinical-pathological features, prognosis, and invasive TME were all associated with Coad mutations. We then developed an LRG_score to predict overall survival (OS) and demonstrated its accuracy as a predictive indicator for COAD patients. We also developed an extremely accurate nomogram chart for the clinical feasibility of LRG_score. Finally, drug sensitivity analysis revealed a strong association between LRG_score and anti-cancer drugs. Conclusion Overall, we identified the prognostic LRG characteristics of COAD patients. This characteristic may help to elucidate the features of TME and explore more effective immunotherapy strategies.

Membranous nephropathy (MN) is the pathology type with the highest incidence of thrombotic events in nephrotic syndrome (NS). While patients with MN are prone to developing thromboembolic complications, the specific mechanism remains unclear. Many studies have shown a high titer of PLA2R antibody aggravates proteinuria and hypoalbuminemia and predicts a lower likelihood of clinical remission in patients with PLA2R-associated MN. Proteinuria and hypoalbuminemia also increase the risk of thrombotic events. In our previous review, we found secretory phospholipase A2 (sPLA2) may act as a ligand for PLA2R, and binding of sPLA2 to PLA2R results in damage to podocytes. sPLA2 can promote the release of AA from membrane phospholipids, and AA is closely related to blood lipid levels and coagulation cascades. The objective of this study is to explain the relationship between phospholipase A2 receptor (PLA2R) and blood hypercoagulability in MN patients and the new theory that secretory phospholipase A2 (sPLA2) and arachidonic acid (AA) may play a role in regulating blood lipid levels and the coagulation cascade in patients with PLA2R-positive MN.Literature retrieval was conducted through China National Knowledge Infrastructure (CNKI) and PubMed. Abstract and Introduction information was then retrieved and the results from the literature searched, classified, and important information summarized. A conclusion was then reached, and a new standpoint put forward.We discussed the role of PLA2R antibody and sPLA2 in hypercoagulability in patients with MN and analyzed the following four possible mechanisms: sPLA2 can combine with PLA2R and induce podocyte apoptosis; sPLA2 may promote the production of anti-PLA2R antibodies; sPLA2 may promote the release of AA from membrane phospholipids; and AA induces platelet aggregation.PLA2R may exacerbate hypercoagulability in patients with PLA2R-related MN, and sPLA2 plays an important role in the process.

Leucine dehydrogenase (LDH) is a NAD+-dependent oxidoreductase, which can selectively catalyze α-keto acids to obtain α-amino acids and their derivatives. It plays a key role in the biosynthesis of L-tert-leucine (L-Tle). As a non-naturally chiral amino acid, L-Tle can be used as an animal feed additive, nutrition fortifier, which is a perspective and important building block in the pharmaceutical, cosmetic, and food additive industry. In this study, four hypothetical leucine dehydrogenases were discovered by using genome mining technology, using the highly active leucine dehydrogenase LsLeuDH as a probe. These four leucine dehydrogenases were expressed in Escherichia coli BL21(DE3), respectively, and purified to homogeneity and characterized. Compared with the other enzymes, the specific activity of PfLeuDH also shows stronger advantage. In addition, the highly selective biosynthesis of L-Tle from trimethylpyruvic acid (TMP) was successfully carried out by whole-cell catalysis using engineered E. coli cells as biocatalyst, which can efficiently coexpress leucine dehydrogenase and formate dehydrogenase. One hundred-millimolar TMP was catalyzed for 25 h, and the yield and space-time yield of L-Tle reached 87.38% (e.e. >99.99%) and 10.90 g L–1 day–1. In short, this research has initially achieved the biosynthesis of L-Tle, laying a solid foundation for the realization of low-cost and large-scale biosynthesis of L-Tle.

Leucine dehydrogenase (LDH) is a NAD+-dependent oxidoreductase, which can selectively catalyze α-keto acids to obtain α-amino acids and their derivatives. It plays a key role in the biosynthesis of L-tert-leucine (L-Tle). As a non-naturally chiral amino acid, L-Tle can be used as an animal feed additive, nutrition fortifier, which is a perspective and important building block in the pharmaceutical, cosmetic, and food additive industry. In this study, four hypothetical leucine dehydrogenases were discovered by using genome mining technology, using the highly active leucine dehydrogenase LsLeuDH as a probe. These four leucine dehydrogenases were expressed in Escherichia coli BL21(DE3), respectively, and purified to homogeneity and characterized. Compared with the other enzymes, the specific activity of PfLeuDH also shows stronger advantage. In addition, the highly selective biosynthesis of L-Tle from trimethylpyruvic acid (TMP) was successfully carried out by whole-cell catalysis using engineered E. coli cells as biocatalyst, which can efficiently coexpress leucine dehydrogenase and formate dehydrogenase. One hundred-millimolar TMP was catalyzed for 25 h, and the yield and space-time yield of L-Tle reached 87.38% (e.e. >99.99%) and 10.90 g L–1 day–1. In short, this research has initially achieved the biosynthesis of L-Tle, laying a solid foundation for the realization of low-cost and large-scale biosynthesis of L-Tle., Graphical Abstract Genome mining of Leucine dehydrogenase and one-pot synthesis of L-tert-leucine from trimethylpyruvic acid.

Fibroblast growth factor 23 (FGF23) plays an important role in the development of chronic kidney disease-mineral bone disorder (CKD-MBD). Abnormally elevated levels of 1,25-dihydroxyvitamin D cause osteocytes to secrete FGF23, which subsequently induces phosphaturia. Recent studies have reported that iron deficiency, erythropoietin (EPO) and hypoxia regulate the pathways responsible for FGF23 production. However, the molecular mechanisms underlying the interactions between FGF23 and anemia-related factors are not yet fully understood. The present review discusses the associations between FGF23, iron, EPO and hypoxia-inducible factors (HIFs), and their impact on FGF23 bioactivity, focusing on recent studies. Collectively, these findings propose interactions between FGF23 gene expression and anemia-related factors, including iron deficiency, EPO and HIFs. Taken together, these results suggest that FGF23 bioactivity is closely associated with the occurrence of CKD-related anemia and CKD-MBD.

The most important challenge in ring-opening polymerization of rac-lactide today is to obtain isotactic PLAs with high molecular weights. The goal of our work is to address this important challenge by developing novel catalysts that enable precise control over stereoselectivity and produce high molecular weight PLAs at the same time. Here we report some rare examples of isoselective magnesium complexes toward the ROP of rac-LA, which are supported by chiral oxazolinyl aminophenolate ligands. Preliminary kinetic investigations confirmed that isotactic PLAs could be achieved via an enantiomorphic site control mechanism by using these chiral magnesium complexes. A pair of racemic magnesium initiators proved to integrate hyperactivity (TOF up to 54 000 h–1 at 25 °C) with sufficient isoselectivity (Pm = 0.80) toward the ROP of rac-LA, leading to the formation of isotactic stereoblock PLA with high molecular weight (Mn = 461 kg mol–1) and a semicrystalline property (Tm = 164 °C). Detailed structural investigati...

Altitude has a significant effect on the combustion of diesel engines during cold start, especially during speed-up. In this study, combustion characteristics of speed-up period were investigated using an experimental test on a heavy-duty diesel engine with an intake and exhaust pressure controlled by the plateau simulation test system to simulate altitude conditions including 0 m, 3000 m and 4500 m. Further effects of altitude on ignition characteristics of diesel engine were accomplished through a zero-dimensional thermodynamic model coupled with a detailed kinetic model. Results indicated that as the altitude rose from 0 m to 3000 m, the pressure in the cylinder was reduced, the number of diesel engine speed-up cycles increased, and the rising speed ratio decreased during speed-up. There was a misfire after the fifth cycle at an altitude of 4500 m, and the rising speed ratio was significantly reduced. Through analysis of fuel injection, air intake and ignition phase, we confirmed that the misfire at the high 4500 m altitude was caused by the ignition delay, which was mainly controlled by chemical reaction during cold start. In the detailed kinetic study, the hot-flame and blue-flame reactions slowed down in the chemical reaction of the mixture as the altitude rose. The higher altitude enhanced the H-atom abstraction, but weakened the second O2 addition and the peroxyalkylhydroperoxide isomerization. The decomposition reaction was enhanced. As a result, the overall reaction rate and the heat release fraction deteriorated, extending significantly the negative temperature coefficient (NTC) duration of the ignition.

Highly isoselective and active ring-opening polymerization of rac-lactide to obtain stereocomplexed polylactide is a long-standing challenge. In this contribution, zinc catalysts with good isoselectivities and high activities (Pm = 0.87, TOF = 3312 h–1 at 25 °C; Pm = 0.92, TOF = 117 h–1 at −20 °C, toluene) for rac-lactide polymerization are reported. These catalysts are coordinated by a well-designed chiral oxazolinyl or achiral benzoxazolyl aminophenolate ligand. Both types of zinc complexes afforded multiblock isotactic PLAs, proving to be formed via a chain-end control mechanism regardless of the existence of a chiral group or not. Preliminary studies suggested that the dihedral angle between the phenoxy and oxazolinyl/benzoxazolyl planes in these complexes reflects the steric bulkiness of the ligand and has a close relation with the isoselectivity of the complex, which might serve as a guide in obtaining new isoselective catalysts of similar types. Furthermore, unprecedented combination of excellent a...

Altitude has a significant effect on combustion of heavy-duty diesel engines, especially during cold start. An experimental study on a heavy-duty diesel engine operating at different altitudes was conducted. Tests were based on a direct injection (DI) turbocharged diesel engine with intake and exhaust pressure controlled by the plateau simulation test system to stimulate altitude conditions including 0 m, 1000 m, 2000 m, 3000 m and 4000 m. Results indicated that the compression and expansion resistance moment reduced and the speed increased during the cranking period. The peak pressure of several cycles was increased during the start-up period; however, the expansion pressure dropped more and the indicated mean effective pressure (IMEP) reduced as the altitude rose. While at an altitude of over 2000 m, the peak pressure fluctuated obviously during the start-up period. The higher the altitude was, the more the fluctuation amplitude and cycle number increased and combustion instability enhanced, which resulted the start-up period time increasing at high altitude. When the altitude rose, the cycle-to-cycle variation of the peak pressure and speed fluctuation increased during the idle, the ignition and CA50 were delayed and the combustion duration was shortened. The effect of altitude on combustion characteristics of the diesel engine was more significant during the start-up period than during its idle period.

One of the ways to meet future emission standards for cars and to limit the peak pressure of a heavy-duty, highly supercharged diesel engine is to reduce the compression ratio. Nevertheless, complications appear because stringent limitations to a reduction in the diesel compression ratio are the start-up requirements, in particular at high altitudes. An experimental study was conducted on the effect of the altitude on the combustion characteristics during the start-up process of a direct-injection midspeed intercooled turbocharged diesel engine with a compression ratio of 14.25:1. Specialized testing was conducted on the low-compression-ratio diesel engine, the intake pressure and the exhaust pressure of which were controlled by a plateau simulation test system to simulate the conditions at altitudes of 0 m, 1000 m, 2000 m, 3000 m, 3750 m and 4500 m. The results indicated that the pressure in the cylinder was lower during the cranking period as the altitude increased and that this caused the ignition operation to become difficult at altitudes above 3000 m. The combustion characteristics are significantly impacted by altitudes above 2000 m. At an altitude of 0–1000 m, the curve pattern of the cycle cylinder pressure had mainly a single peak during the start-up period. When the altitude increased to 2000 m, twin peaks and afterburn appeared in the cycles. Misfire appeared during the start-up period when the altitude increased to 3000 m, the combustion instability increased and the average indicated mean effective pressure decreased rapidly. When the altitude increases, the cycle-to-cycle variations in the peak pressure increased during idle, the ignition and the crank angle position at 50% of the cumulative heat release rate were delayed and the combustion duration was extended.

The mono- and dinuclear salen aluminum complexes L1–3AlMe (1, 2, 5), L2AlOiPr (3), L2AlOBn (4) and L1–3Al2Me4 (6–8) (L = 6,6′-[(6,6′-dimethyl-[1,1′-biphenyl]-2,2′-diyl)bis(nitrylomethilidyne)]-bis(2-R1-4-R2-phenol): L1, R1 = R2 = Me; L2, R1 = tBu, R2 = Me; L3, R1 = R2 = cumyl) with a racemic 6,6′-dimethylbiphenyl bridge were tested as initiators for the copolymerization of L-LA and e-CL. In the presence of alcohol, the mononuclear aluminum complexes catalyzed the controlled copolymerization in the melt at 110 °C, producing practically random copolymers with narrow polydispersity indices (Đ = 1.03–1.07). Notably, the component of the copolymer produced by complex 3 strictly correlated with the feed ratio of the monomers at different stages of the copolymerization. In a 50/50 feed ratio of L-LA/e-CL, the reactivity ratios of the two monomers are rLA = 1.17, rCL = 0.80. The average lengths of the lactidyl and caproyl sequences in the resultant copolymer are LLA = 1.91, LCL = 1.93. Even at 180 °C, the copolymerization initiated by complex 3 was still well-controlled, producing random copolymers with narrow dispersity indices (Đ = 1.07–1.09). Compared with the mononuclear counterparts, the dinuclear aluminum methyl complexes enable a few fold boost in activity because of the lower steric hindrance around the aluminum centers, but gave tapered copolymers with broadened Đ values (Đ = 1.12–1.22).

A series of tridentate achiral benzoxazolyl-based aminophenolate zinc complexes, LZnN(SiMe3)2 (L = 2-{[benzoxazoly-CH2N(R3)-]CH2}-6-R1-4-R2-C6H2O, R1 = R2 = Cl, R3 = Bn (1); R1 = R2 = tBu, R3 = Bn (2); R1 = trityl, R2 = Me: R3 = Bn (3); R3 = phenethyl (4); R3 = 3-methylbutyl (7); R3 = n-hexyl (8); R3 = cyclopentyl (9); R3 = cyclooctyl (11); R3 = 1-adamantyl (12)), was synthesized via the reactions of Zn[N(SiMe3)2]2 and 1 equiv of the corresponding aminophenol proligands. All of the complexes were obtained as racemates, and the X-ray diffraction studies confirmed the monomeric structures of typical complexes 11 and 12, where the metal center is tetra-coordinated by three donors of the aminophenolate ligand and one silylamido group. All of the complexes proved to be efficient initiators for the ring-opening polymerization of rac-lactide (rac-LA) at ambient temperature, and the polymerizations were better controlled in the presence of 2-propanol. The substituents on the ortho-position of the phenoxide unit o...

In this paper, we mainly consider the augmented Lagrangian duality theory and explore second-order conditions for the existence of augmented Lagrange multipliers for eigenvalue composite optimization problems. In the approach, we reformulate the augmented Lagrangian introduced by Rockafellar into a new form in terms of the Moreau envelope function and characterize second-order conditions via the epi-derivatives of the augmented Lagrangian.

In this paper, augmented Lagrangian duality is considered for composite optimization problems, and first- and second-order conditions for the existence of augmented Lagrange multipliers are presented. The analysis is based on the reformulation of the augmented Lagrangian in terms of the Moreau envelope functions and the technique of epi-convergence via the calculation of second-order epi-derivatives of the augmented Lagrangian. It is also proved that the second-order conditions for optimization problems with abstract constraints given in a form of set inclusions, obtained by Shapiro and Sun, can be derived directly from our general results.

Cold starting test of a high pressure common rail diesel engine was conducted on an engine test bench simulating plateau environment with high altitudes and low temperature. A comprehensive study of cold starting and idling performance was investigated under plateau ambient temperature of-35°C to-10°C and altitude ranged from 2km to 4km. Results show that, without inlet air heating, during engine starting up under different altitude at-10°C, average inlet temperature and pressure can drop slightly and idling rotating speed exhibits strong fluctuation. By heating up inlet air for 60 seconds, the inlet temperature shows statistically linear growing trend in the first 8 heating seconds, during which period averaged inlet temperature rises to 12.4°C, thus obviously lifting up intake temperature, improving engine starting up performance and reducing rotating speed fluctuation. At high altitude and cold plateau conditions, by prolonging the air heating time solely has limited effects on reducing engine starting up time or improving cold starting performance, nor can rotating speed fluctuation been effectively reduced. When ambient temperature reaches-30°C, by heating up inlet air for the same specified time interval, an average of temperature rise of 2.4°C can be obtained for altitude step increase of 1 kilometer, but cold starting up performance has not been therefore significantly improved.

In this paper, particulate numbers were measured from an in-service PASSAT passenger car fueled with blends of biodiesel and China Phase IV diesel in different ratios using EEPS-3090 (Engine Exhaust Particle Sizer) Spectrometer. Fuel blends composited of 5%, 10%, 20%, 50% and 100% biodiesel were used and nominated as B5, B10, B20, B50 and B100, respectively. A total average speed of 31 km/h was observed, and for urban arterial roads and suburban freeways, average speed displayed an individual magnitude of 19.7km/h and 72km/h. After using blends of biodiesel/diesel, particulate mass emission factors displayed different reduction percentages. For particulate number emission factors, increasing trend was observed on city arterial roads and a declining trend for sub streets in urban and suburban areas. Particulate numbers emission exhibited normal distribution on suburban highways, while bi-normal distribution was revealed for other types of roads. With higher biodiesel/diesel blending ratios, particulate number in accumulated mode from passenger car exhaust showed lower value but higher value for nuclei mode, and the center size for peak particulate number emissions moved towards smaller scales.

The synthesis and characterization of aluminum alkyl and alkoxide complexes bearing racemic 6,6′-dimethylbiphenyl-bridged salen-type ligands, and their catalysis in the ring-opening polymerization (ROP) of rac-lactide are reported. Reactions of AlMe3 with various amounts of the proligands L1−4H2 (6,6′-[(6,6′-dimethyl-[1,1′-biphenyl]-2,2′-diyl)bis(nitrylomethilidyne)]-bis(2-R1-4-R2-phenol): L1H2, R1 = R2 = Me; L2H2, R1 = tBu, R2 = Me; L3H2, R1 = R2 = cumyl; L4H2, R1 = Br, R2 = tBu) afforded the corresponding mono- and dinuclear aluminum methyl complexes [L1−3AlMe (1–3), L1−4Al2Me4 (4–7)]. Aluminum alkoxide complexes L2AlOiPr (8), L2AlOBn (9), and α-alkoxy ester complexes L2Al(OCMe2CO2Me) (10), L2Al[(S)-OCHMeCO2Me] (11) were prepared via in situ alcoholysis of the parent aluminum methyl complex 2 with the corresponding alcohols. The molecular structures of mononuclear complexes 1–3, dinuclear complex 6, alkoxide complexes 8–9 and α-alkoxy ester complexes 10–11 were established by single-crystal X-ray diffraction studies. Two broad resonances at about 69–70 ppm and 25–41 ppm were observed in the 27Al NMR spectra of complexes 10 and 11, indicating the existence of both four- and five-coordinate aluminum centers in solution, which results from the dissociation of one N donor of the salen ligand, accompanied by an association and dissociation equilibrium of the carbonyl group of the α-alkoxy ester ligand to the aluminum center. Complex 11 is also a rare example of an O-lactate model complex that mimics the first insertion of L-LA. All complexes were investigated for the ROP of rac-LA at 110 °C in toluene. The polymerization initiated by complexes 1–3 in the presence of iPrOH showed living features, affording PLAs with narrow molecular weight distributions (PDIs = 1.03–1.05) and 65–73% isotacticities. Particularly, complex 8 showed an “immortal” behavior for the polymerization of rac-LA in the presence of excess alcohol. Compared with the mononuclear counterparts, the tetra-coordinate dinuclear aluminum complexes enabled a few fold boosts in activity, but gave atactic PLAs with broadened PDIs.

In this paper, we explore some properties of the Moreau envelope function e λ f ( x ) of f and the associated proximal mapping P λ f ( x ) in the sense of the Bregman distance induced by a convex function g . Precisely, we study the continuity, differentiability, and Clarke regularity of the Moreau envelope function and the upper semicontinuity and single-valuedness of the proximal mapping as well as its relation to the convexity of λ f + g , where λ is a positive parameter.

The present study elaborates a cost-effective and transfectant-free method for generating recombinant Bombyx mori (silkworm) nucleopolyhedrovirus in silkworm larvae and pupae by injecting invasive Escherichia coli carrying BmBacmid [BmNPV (B. mori nucleopolyhedrovirus)—Bacmid] into larval haemocoel. Up to 10 9 PFU (plaque-forming units)/ml of infective recombinant baculovirus was generated in the silkworm by intrahaemocoelic injection with 10 6 DAP (diaminopimelic acid) auxotrophic and BmBacmid containing E. coli cells expressing both invasin and listeriolysin. Thus I ml of overnight culture of E. coli is sufficient to inject more than 2000 larvae, while DAP costing up to $I is enough to inject about 4000 larvae. Recombinant proteins can be controlled to be expressed mainly in pupae by adjusting the injection dose, too. In this new method, many original manipulations have been eliminated, including BmBacmid preparation and the subsequent complex transfection procedures. Hence it is a time- and cost-saving means for large-scale injection of B. mori for recombinant baculovirus production in comparison with the traditional transfection methods, which may play an important role in the industrial development of the BmNPV—silkworm bioreactor.

Developing cost-effective methods for high throughput production of recombinant baculoviruses in insect cells is very challenging, because the baculovirus DNA preparation and the following transfection procedure are labour-intensive and time consuming. We developed a new method of introducing recombinant Bacmid DNA from bacteria into insect cells simply using invasive diaminopimelate (DAP) auxotrophic Escherichia coli to infectSpodoptera frugiperda 9 cells. The E. coli cells with recombinant Bacmids enter insect cells with the help of the invasion factor from Yersinia pseudotubercolusis. Without DAP in medium, the cell wall of DAP auxotrophic E. coli cannot be synthesized so that the bacterial cell will disrupt and release recombinant Bacmid. The released Bacmids will generate infective recombinant baculovirus particles in insect cells. We combined this E. coli invasion method with the zero background transposition system to generate recombinant baculovirus in a rapid and simple way. Without preparation and purification of recombinant Bacmids from E. coli and the labour-intensive and complex transfection procedure, this transfection reagent free method enables a convenient and economic high throughput production of recombinant baculoviruses.

In this study, a 15-mer phage display peptide library was employed to pan against human rotavirus immobilized on solid phase. 4 different peptides were selected and could bind with rotavirus particles specifically. Plaque reduction neutralization test and MTT analysis results indicated that 3 of the peptides can inhibit rotavirus infecting in vitro. A peptide which sequence is QSNPIHIITNTRNHP showed the best efficiency--93% neutralization infectivity. Two other peptides, A and B, showed 40% and 50% neutralization infectivity respectively. Amino sequence analysis results indicate the 3 peptides containing 2 conserved motifs: SNPIHII and NIP. No putative trypsin hydrolysis site was found in C peptide, however, 4 and 3 potential sites were found in A and B peptides respectively. Using trypsin inhibitor, both A and B peptides showed the similar antiviral effect as that of C peptide. It suggests that the intactness of the 2 conserved motifs play an important role in counteracting virus infection. According to the results of this study, peptide C is hopeful to be exploited as an antiviral peptide drug.

This letter introduces a polycrystalline-silicon nanowire (NW) thin-film nonvolatile memory (NVM) with a self-assembled silicon-nanocrystal (Si-NC) embedded charge-trapping (CT) layer. This process is simple and compatible with conventional CMOS processes. Experimental results indicate that this NW NVM exhibits high reliability due to a deep-quantum-well structure and immunity of enhanced electric field underneath a disk-shaped Si-NC. After 10 000 P/E cycles, the memory window loss of the NVM with a Si-NC embedded CT layer is less than 12% until 104 s at 150 °C. Accordingly, a poly-Si thin-film transistor with a Si-NC embedded CT layer is highly promising for NVM applications.

In this paper, we consider the use of orthogonal moments for invariant classification of alphanumeric characters of different size. In addition to the Zernike and pseudo-Zernike moments (ZMs and PZMs) which have been previously proposed for invariant character recognition, a new method of combining Orthogonal Fourier–Mellin moments (OFMMs) with centroid bounding circle scaling is introduced, which is shown to be useful in characterizing images with large variability. Through extensive experimentation using ZMs and OFMMs as features, different scaling methodologies and classifiers, it is shown that OFMMs give the best overall performance in terms of both image reconstruction and classification accuracy.