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5-methyl-2-hexanone is used as a versatile polymerization solvent for industrial preparation processes of bulk and fine chemicals. An efficient catalyst, Pd/γ-Al2O3, is reported for the preparation of 5-methyl-2-hexanone by selective hydrogenation of 5-methyl-3-hexen-2-one. The catalyst exhibits remarkable activity and selectivity even at atmospheric pressure and low temperature (1 atm, 80 °C). The influence weight of reaction conditions on the reaction process was obtained through the Artificial Neural Network model, which were reaction pressure, reaction temperature and liquid hourly space velocity in order. The reaction kinetics and mechanism of 5-methyl-2-hexanone preparation by hydrogenation over Pd/γ-Al2O3 catalyst were investigated. The hydrogenation reaction pathway of 5-methyl-3-hexen-2-one was obtained by using Density functional theory calculations, and the mechanism of selective hydrogenation of CC double bonds and CO double bonds was revealed. A kinetic model based on the LHHW model assumption was also proposed and compared with experimental results demonstrating good predictability.
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Immune checkpoints inhibitors are effective but it needs more precise biomarkers for patient selection. We explored the biological significance of LINC00862 in pan-cancer by bioinformatics. And we studied its regulatory mechanisms using chromatin immunoprecipitation and RNA immunoprecipitation assays etc. TCGA and single-cell sequencing data analysis indicated that LINC00862 was overexpressed in the majority of tumor and stromal cells, which was related with poor prognosis. LINC00862 expression was related with immune cell infiltration and immune checkpoints expression, and had a high predictive value for immunotherapy efficacy. Mechanistically, LINC00862 competitively bound to miR-29c-3p to unleash SIRT1's tumor-promoting function. SIRT1 inhibitor-EX527 were screened by virtual screening and verified by in vitro and vivo assays. Notably, acetyltransferase P300-mediated super-enhancer activity stimulated LINC00862 transcription. Collectively, LINC00862 could be a diagnostic and prognostic biomarker. LINC00862 could also be a predictive biomarker for immunotherapy efficacy. Super-enhancer activity is the driver for LINC00862 overexpression in cervical cancer and gastric cancer.
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Artificially molding exciton flux is the cornerstone for developing promising excitonic devices. In the emerging hetero/homobilayers, the spatial separated charges prolong exciton lifetimes and create out-plane dipoles, facilitating electrically control exciton flux on a large scale, and the nanoscale periodic moiré potentials arising from twist-angle or/and lattice mismatch can substantially alter exciton dynamics, which are mainly proved in the heterostructures. However, the spatially indirect excitons dynamics in homobilayers without lattice mismatch remain elusive. Here the nonequilibrium dynamics of indirect exciton in homobilayers are systematically investigated. The homobilayers with slightly twist-angle can induce a deep moiré potential (>50 meV) in the energy landscape of indirect excitons, resulting in a strongly localized moiré excitons insulating the transport dynamics from phonons and disorder. These findings provide insights into the exciton dynamics and many-body physics in moiré superlattices modulated energy landscape, with implications for designing excitonic devices operating at room temperature.
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Zeolite is considered an ideal catalyst for olefin hydration due to its high specific surface area and abundant acid sites. However, the immiscibility of the water-oil two phases in olefin hydration limits mass transfer, and the side reaction of etherification occurs acutely, resulting in a low yield of alcohol. Thus, water-oil amphiphilic HZSM-5 was prepared by sulfonating silanized zeolite. The successful introduction of organic and sulfonic acid groups is demonstrated by FT-IR, TG, and water contact angles. Amphiphilic HZSM-5 can stabilize the Pickering emulsion and catalyze cyclopentene hydration at the phase interface. In addition, NH3-TPD and Py-IR show that the amount of strong BroÌ·nsted acid sites of zeolites increases significantly after sulfonation. This facilitates the rate-determining step of cyclopentene activation by H+ to form carbocation. Moreover, the nucleophilic side reactions are inhibited by a high concentration of H+. Finally, under the optimized reaction condition, the conversion of cyclopentene can achieve 5.066% with a selectivity of 85.37% to cyclopentanol, which almost reaches the reaction equilibrium.
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Heavy metal contamination severely affects the aquatic environment and organisms. Copper (Cu) and cadmium (Cd) are two of the most common heavy metal contaminants that impair the survival, development, and reproduction of aquatic organisms. With the growth of agriculture and industry, there is a possibility of heavy metal pollution in Coregonus ussuriensis Berg's water source. However, there are no published studies on the toxicity to C. ussuriensis. Acute toxicity experiments in C. ussuriensis revealed the 96-h median lethal concentrations of copper and cadmium to be 0.492 mg·L-1 (95% confidence interval: 0.452-0.529) and 1.548 mg·L-1 (95% confidence interval: 1.434-1.657), respectively, and safe concentrations of 4.92 µg·L-1 and 15.48 µg·L-1, respectively. C. ussuriensis was then treated for 96 h with Cu (20% of 96 h LC50), Cd (20% of 96 h LC50), and a combination of Cu and Cd (20% of Cu 96 h LC50 + 20% of Cd 96 h LC50). The histological damage caused by the three different exposure modes to the liver and gills of C. ussuriensis was verified using hematoxylin and eosin staining. All three exposure modes caused different degrees of vacuolization, nuclear consolidation, and necrosis in the liver tissue of C. ussuriensis and edema, hyperplasia, laminar fusion, and epithelial elevation in the gill tissue compared with the reference group. The severity of the damage increased with increasing exposure time. Anti-oxidant activity in the gill and liver tissues were measured using enzyme activity assay kits to reflect oxidative stress induced by copper and cadmium exposure alone and in combination. The enzyme activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH) were substantially higher than those in the reference groups. However, the activities of the enzymes decreased with increasing exposure time. Malondialdehyde (MDA) activity significantly increased during exposure in relation to that in the reference group. Analysis of immune gene expression in C. ussuriensis gill and liver tissues was executed using real-time inverse transcript polymerase chain response (RT-PCR). The expression levels of the pro-inflammatory cytokines interleukin one beta (IL-1ß) and tumor necrosis factor-alpha (TNF-α) were positively correlated with exposure time and were significantly upregulated with increasing exposure time. Metallothionein (MT) gene expression levels were significantly upregulated in the short term after exposure compared to the reference group but decreased with increasing exposure time. Our results indicate that exposure to aqueous copper and cadmium solutions, either alone or in combination, causes histopathological damage, oxidative stress, and immunotoxicity in C. ussuriensis gill and liver tissue. This study investigated the toxic effects of copper and cadmium on C. ussuriensis to facilitate the monitoring of heavy metals in water sources for healthy aquaculture.
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The difference in grain yield between superior grains (SG) on the upper part and inferior grains (IG) on the lower part of the same panicle was widely reported. To date, variations in rice taste quality between SG and IG and the related starch physicochemical properties remained poorly understood. Here, rice cultivars with different taste quality (NT, normal taste; GT, good taste) were grown to investigate the mechanism underlying taste difference between SG and IG and the correlation between cooked rice taste and starch properties. In this study, the taste value of GT rice was 32.2% higher than that of NT rice across the cultivars. The GT rice comprised a series of typical taste qualities of larger stickiness, smaller hardness, lower apparent amylose content (AAC), and lower protein content (PC). The taste quality differed among rice grains on the same panicle; SG achieved 21.9% and 17.0% higher taste value than IG in GT rice and NT rice, respectively. The higher taste value in SG was owing to the larger stickiness and lower PC. Meanwhile, SG of GT rice achieved the lowest PC (8.2%) and gluten content (5.6%), which might indicate a better health value. Additionally, larger and smoother granules, more fa (DP < 12), lower crystallinity, and larger 1045/1022 cm-1 ratios were found in SG starch compared to IG starch. These led to a weaker swelling power and lower gelatinization enthalpy in SG starch, while gelatinization temperature and retrogression enthalpy were the opposite. Moreover, SG starch exhibited higher storage modulus, loss modulus, slowly digestible starch contents, and resistant starch contents than IG. Our results revealed a great difference in taste quality between SG and IG in rice. The larger and smoother starch granules and shorter chain length could increase the ordered structure of starch, thus improving swelling power, gelatinization properties, and rheological characteristics and facilitating better taste quality of SG over IG. Besides, the lower PC (especially gluten content), higher slowly digestible starch, and higher resistant starch content indicated a more promising health value of SG in the food industry.
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Oryza , Almidón , Almidón/química , Oryza/química , Gusto , Almidón Resistente/metabolismo , Glútenes/metabolismoRESUMEN
The ability to precisely regulate the size of a nanogap is essential for establishing high-yield molecular junctions, and it is crucial for the control of optical signals in extreme optics. Although remarkable strategies for the fabrication of nanogaps are proposed, wafer-compatible nanogaps with freely adjustable gap sizes are not yet available. Herein, two approaches for constructing in situ adjustable metal gaps are proposed which allow Ångstrom modulation resolution by employing either a lateral expandable piezoelectric sheet or a stretchable membrane. These in situ adjustable nanogaps are further developed into in-plane molecular break junctions, in which the gaps can be repeatedly closed and opened thousands of times with self-assembled molecules. The conductance of the single 1,4-benzenediamine (BDA) and the BDA molecular dimer is successfully determined using the proposed strategy. The measured conductance agreeing well with the data by employing another well-established scanning tunneling microscopy break junction technique provides insight into the formation of molecule dimer via hydrogen bond at single molecule level. The wafer-compatible nanogaps and in-plane dynamical break-junctions provide a potential approach to fabricate highly compacted devices using a single molecule as a building block and supply a promising in-plane technique to address the dynamical properties of single molecules.
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Ultra-wide slabs have a good application market and prospect, but there is still a lack of research on the flow field. To explore the characteristics of its flow field, this study built a 0.5-scale physical model of mold using Perspex. The effect of casting speed on flow field and surface flow speed was investigated by using an ink tracer experiment and contact measurement. There were various flow patterns in the ultra-wide slab mold, and they continue to transform each other. The jet momentum from the nozzle ports was diffused by colliding with the wide face, which lowered its kinetic energy and affected its subsequent diffusion. Compared with the conventional mold, the upper flow intensity of the ultra-wide slab mold was weaker, which made its liquid surface inactive and caused it to produce a flux rim or slag strip. At different casting speeds, the average flow speed distribution of the ultra-wide slab was C-shaped. When it increased from 0.9 to 1.4 m/s, the corresponding maximum average flow speed increased from 0.08 to 0.2 m/s. At the same time, the proportion of the low-flow speed zone at the most active part of the surface also gradually decreased from more than 90% to about 49%.
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Chronic kidney diseases usually cause renal interstitial fibrosis, the prevention, delay, and treatment of which is a global research hotspot. However, no definite treatment options are available in modern medicine. Chinese herbal medicine has a long history, rich varieties, and accurate treatment effects. Hitherto, many Chinese herbal medicine studies have emerged to improve renal interstitial fibrosis. This paper reviews the mechanisms of renal interstitial fibrosis and recent studies on the disease intervention with Chinese herbal medicine through literature search, intend to reveal the importance of Chinese herbal medicine in renal interstitial fibrosis. The results show that Chinese herbal medicine can improve renal interstitial fibrosis, and the effects of Chinese herbal medicine on specific pathological mechanisms underlying renal interstitial fibrosis have been explored. Additionally, the limitations and advantages of Chinese herbal medicine in the treatment of renal interstitial fibrosis, possible research directions, and new targets of Chinese herbal medicine are discussed to provide a basis for studies of renal interstitial fibrosis.
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High efficient removal of antibiotics during nutriments recovery for biomass production poses a major technical challenge for photosynthetic microbial biofilm-based wastewater treatment since antibiotics are always co-exist with nutriments in wastewater and resist biodegradation due to their strong biotoxicity and recalcitrance. In this study, we make a first attempt to enhance metronidazole (MNZ) removal from wastewater using electrochemistry-activated binary-species photosynthetic biofilm of Rhodopseudomonas Palustris (R. Palustris) and Chlorella vulgaris (C. vulgaris) by cultivating them under different applied potentials. The results showed that application of external potentials of -0.3, 0 and 0.2 V led to 11, 33 and 26-fold acceleration in MNZ removal, respectively, as compared to that of potential free. The extent of enhancement in MNZ removal was positively correlated to the intensities of photosynthetic current produced under different externally applied potentials. The binary-species photoelectrogenic biofilm exhibited 18 and 6-fold higher MNZ removal rate than that of single-species of C. vulgaris and R. Palustris, respectively, due to the enhanced metabolic interaction between them. Application of an external potential of 0V significantly promoted the accumulation of tryptophan and tyrosine-like compounds as well as humic acid in extracellular polymeric substance, whose concentrations were 7.4, 7.1 and 2.0-fold higher than those produced at potential free, contributing to accelerated adsorption and reductive and photosensitive degradation of MNZ.
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Chlorella vulgaris , Microalgas , Purificación del Agua , Biopelículas , Matriz Extracelular de Sustancias Poliméricas , Metronidazol/análisis , Aguas ResidualesRESUMEN
Neurofibromatosis type 1 (NF1) is an autosomal dominant tumor predisposition syndrome that involves the central and peripheral nervous systems. Accurate detection and segmentation of neurofibromas are essential for assessing tumor burden and longitudinal tumor size changes. Automatic convolutional neural networks (CNNs) are sensitive and vulnerable as tumors' variable anatomical location and heterogeneous appearance on MRI. In this study, wepropose deep interactive networks (DINs) to address the above limitations. User interactions guide the model to recognize complicated tumors and quickly adapt to heterogeneous tumors. We introduce a simple but effective Exponential Distance Transform (ExpDT) that converts user interactions into guide maps regarded as the spatial and appearance prior. Comparing with popular Euclidean and geodesic distances, ExpDT is more robust to various image sizes, which reserves the distribution of interactive inputs. Furthermore, to enhance the tumor-related features, we design a deep interactive module to propagate the guides into deeper layers. We train and evaluate DINs on three MRI data sets from NF1 patients. The experiment results yield significant improvements of 44% and 14% in DSC comparing with automated and other interactive methods, respectively. We also experimentally demonstrate the efficiency of DINs in reducing user burden when comparing with conventional interactive methods.
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Artrogriposis , Neurofibromatosis 1 , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Redes Neurales de la Computación , Neurofibromatosis 1/diagnóstico por imagen , Carga TumoralRESUMEN
Osteosarcoma is a type of tumor originating from the bone cells, most often from long bones. Children and adolescents are mainly affected by osteosarcoma. Identifying the condition with osteosarcoma is mandatory to provide proper treatment to the affected patients. This research work has introduced an identification of an osteosarcoma biomarker "miRNA-21" on the interdigitated electrochemical sensor by nuclease digestion. The target RNA sequence of miRNA-21 was hybridized to the capture DNA and placed on the sensing electrode surface with the aid of the biotin-streptavidin interaction. The unhybridized immobilized single-standard capture DNA was digested by S1-nuclease. The current response of the digestion level was considered as the duplex formation between the target and capture DNA. Using this technique, the detection limit of the target was reached to 1 fM and a similar response of current was noted with the target RNA-spiked human serum, indicating the selective identification of target RNA. Further, single mismatched, triple mismatched, and random miRNA sequences (miRNA-195) failed to interact with the immobilized capture DNA, representing the specific identification of target RNA. This nuclease digestion technique with miRNA-21 identification helps in detecting osteosarcoma and related issues.
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Técnicas Biosensibles , MicroARNs , Osteosarcoma , Adolescente , Técnicas Biosensibles/métodos , Niño , ADN , Digestión , Técnicas Electroquímicas/métodos , Electrodos , Humanos , Límite de Detección , Osteosarcoma/diagnósticoRESUMEN
Novel core-shell nanostructure electrodes benefit from the excellent properties of their constituent materials, as well as the synergy between them. However, it is challenging to fabricate such structures efficiently. In this study, NiSe nanorods were fabricated using Ni foam as the conductive substrate and reactant via a one-step hydrothermal process, and Ni(OH)2nanosheets were coated on the surface of the nanorods via one-step electrodeposition. The effect of the structure and morphology on the properties of the material was explored using scanning electron microscopy, x-ray diffraction, and electrochemical technology. The obtained core-shell NiSe/Ni(OH)2exhibited an areal capacity of 1.89 mAh cm-2at a current density of 5 mA cm-2. The assembled NiSe/Ni(OH)2//AC hybrid supercapacitor exhibited excellent energy and power densities, indicating that NiSe/Ni(OH)2has great potential for use as a battery-type electrode in energy storage systems.
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Development of economic strategy to synthesize hollow zeolite with widely tunable Si/Al ratios providing variable acidity is of great significance in industry. Here, a one-step and low-cost strategy without mesoporogen was successfully developed to synthesize single-crystal hollow ZSM-5 containing mesopores/macropores, with variable Si/Al ratios of about 14-∞ and 114-∞ at critical TPA+/SiO2 ratios of 0.05-0.1 and 0.05, respectively. This is the first time the usage of a large amount of TPAOH was avoided while breaking the traditional limitation of Si/Al ratio (25-50). The component of synthesis system and crystallization temperature acting as the vital roles in hollow structure has been confirmed by a series of characterization. Moreover, according to the investigation of the evolution process, a novel racing crystallization mechanism based on the competition relationship between surface crystallization and the internal dissolution rate was proposed for the first time. The racing crystallization mechanism and internal nonprotective aluminum become the crucial factors for synthesis. The prepared hollow ZSM-5 zeolites exhibit superior catalytic performance in the different acidity-catalyzed condensation involving large molecules between benzaldehyde and n-butyl alcohol as well as 2-hydroxyacetophenone, which is mainly attributed to the property acidity, more accessible active Al sites on the surface, and shorter diffusion path. By calculating, the effectiveness factor (η) of hollow zeolite is close to 1, further confirming its better mass transfer ability. The strategy has also been successfully extended to the synthesis of high-amount Fe-doped, Ga-doped, and B-doped hollow silicate-1.
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The gonadal development; edible tissue ratio; and proximate, fatty acid, and free amino acid composition were examined and compared among Eriocheir sinensis samples from four sources. The gonadosomatic index (GSI) of Heilongjiang (HLJ) crabs was significantly higher than that of the other crabs from September to October (P < 0.05). Of all the edible tissues of E. sinensis, HLJ crab had the highest linolenic acid (18:3n3, LNA) and arachidonic acid (20:4n6, ARA) contents (P < 0.05), while Qinghai (QH) crab had the highest eicosapentaenoic acid (20:5n3, EPA) content (P < 0.05). The highest docosahexaenoic acid (22:6n3, DHA) and DHA/EPA contents were observed in Shandong (SD) crabs (P < 0.05), and the highest linoleic acid (18:2n6, LA) content was found in Shanghai (SH) crabs (P < 0.05). In conclusion, E. sinensis inhabiting relatively low-temperature regions (northern China) can initiate gonadal development earlier, and the quality of E. sinensis living in paddies and lakes is better than that of crabs living in ponds.
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Aminoácidos/análisis , Braquiuros/crecimiento & desarrollo , Braquiuros/metabolismo , Ácidos Grasos/análisis , Gónadas/crecimiento & desarrollo , Alimentos Marinos/análisis , Aminoácidos/metabolismo , Animales , China , Ácidos Grasos/metabolismo , Análisis de los Alimentos , Gónadas/metabolismoRESUMEN
A flower-like structured electrode material of Co3O4@Ni-Co layered double hydroxide (LDH) grown on Ni foam (Co3O4@Ni-Co LDH/NF) was prepared via anin situgrowth, annealing and electrodeposition process. The Co3O4@Ni-Co LDH/NF electrode was prepared with the optimized conditions of annealing temperature 300 °C, deposition time 20 min and Ni/Co ratio 1:1. The results showed that the as-prepared electrode material exhibited an excellent specific capacitance and great cycling stability. Furthermore, an quasi-solid-state supercapacitor was assembled using the prepared Co3O4@Ni-Co LDH/NF as the positive electrode and activated carbon on Ni foam (AC/NF) as the negative electrode. The as-assembled device presented a high energy density and power density.
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The ZnCo2O4@NiCo2S4@PPy core-shell nanosheets material is prepared by directly growing leaf-like ZnCo2O4 nanosheets derived from the metal-organic framework (MOF) on Ni foam (NiF) via chemical bath deposition and annealing methods and then combining with NiCo2S4 and PPy via electrodeposition methods. The special core-shell structure formed by MOF-derived ZnCo2O4, NiCo2S4 and PPy creates a bi-interface, which could significantly promote the contact between electrode and electrolyte, provide more active sites and accelerate electron/ion transfer. And the combination of these three materials also produces a strong synergistic effect, which could further improve the capacitive performance of the electrode. Therefore, the ZnCo2O4@NiCo2S4@PPy/NiF electrode exhibits the maximum areal capacitance (3.75 F cm-2) and specific capacitance (2507.0 F g-1) at 1 mA cm-2 and 0.5 A g-1, respectively. Moreover, its capacitance retention rate is still 83.2% after 5000 cycles. In addition, a coin-type hybrid supercapacitor is assembled and displays a high energy density of 44.15 Wh kg-1 and good cycling performance.
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Osteosarcoma, a malignant tumor of bones, has very high incidence in adolescents and young people. The present study investigated the effect of indirubin-3'-oxime (IDR3O) derivative on proliferation of osteosarcoma cells in vitro and tumor growth in vivo. Changes in growth and induction of apoptosis in osteosarcoma cells were assessed using WST-8 and TUNEL staining assays. Treatment of MG63 and Saos2 cells with IDR3O inhibited proliferation, activated apoptosis and promoted AMPK-activation. In IDR3O treated MG63 and Saos2 cells PGC-1α (Peroxisome proliferator-activated receptor-γ coactivator-1α) levels were markedly promoted compared to control (untreated) cells. In the mice model osteosarcoma was induced by implantation of 2 × 106 MG63 cells on dorsal side subcutaneously. Then the experimental group of mice received IDR3O intra-peritoneally during 45 days. IDR3O-treatment suppressed tumor development significantly compared to control (untreated) group but didn't changed body weight. IDR3O inhibits osteosarcoma cell growth and activates apoptosis through AMPK dependent pathway. Therefore, IDR3O may be considered for treatment of osteosarcoma as it effectively arrests tumor growth in mice.
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Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas de Unión al ADN/metabolismo , Indoles/farmacología , Proteínas Mitocondriales/metabolismo , Osteosarcoma/tratamiento farmacológico , Oximas/farmacología , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Factores de Transcripción/metabolismo , Proteínas Quinasas Activadas por AMP/genética , Animales , Apoptosis/efectos de los fármacos , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proteínas de Unión al ADN/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Proteínas Mitocondriales/genética , Osteosarcoma/metabolismo , Osteosarcoma/patología , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Transducción de Señal , Factores de Transcripción/genética , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
INTRODUCTION: To report about the successful outbreak containment of COVID-19 in Shantou, one of the prefectural cities of Guangdong province in the mainland China. METHODOLOGY: All patients confirmed as having COVID-19 between 23 January and 25 March 2020 by RT-PCR assay in the clinical lab of Shantou CDC were included and divided into three groups based on the source of identification: hospital diagnosis, contact tracing, and community screening. Collected data was analyzed and compared among these three groups. RESULTS: A total of 25 COVID-19 cases were identified in Shantou. The first case was identified on 14 January 2020 at one of two COVID-19 dedicated hospitals in Shantou. The majority of the cases were either imported from Wuhan or linked to Wuhan/Hubei. The median lag time for diagnosis (i.e., the time between symptom onset and case confirmation) was 2 days (IQR, 2.0-4.0) for all cases, 9 days (IQR, 7.0-10.0) for the cases diagnosed in hospitals, 2 days (IQR, 1.5-2.0) for the cases in contact tracing, and 4 days (IQR, 2.5-4.5) for cases in community screening, with a significantly longer diagnosis lag time in hospitals (p = 0.003). Multivariate linear regression models showed larger family size and severe cases as the significant predictor for increasing number of close contacts. CONCLUSIONS: The current pandemic appears to exist for an uncertain period. The early containment measures applied in Shantou, a city with insufficient healthcare resources for COVID-19, seems to be appropriate for cities or areas with similar profiles.