Key Determinant Factors Research Articles

Monte Carlo investigation of the effect of gold nanoparticles’ distribution on cellular dose enhancement

PurposeIn recent decades‎, ‎radiotherapy has became one of the most useful and cost effective tools in cancer treatment‎. Having a number of unique characteristics made gold nanoparticles (GNPs) as promising candidates in achieving dose enhancement in tumor and improving the radiation treatment outcome‎. ‎Considering the widely documented tendency of GNPs to localize around the nucleus‎, ‎the distribution model of GNPs in the medium needs to be investigated in detail and to be well quantified‎. MethodsThe MCNPX Monte Carlo code was used to simulate particle transport in cells‎. ‎A single cell‎, ‎including an ellipsoidal cytoplasm with a centrally located sphere surrounded by a cube as the medium was modeled‎. ‎The physical dose due to the irradiation of 10–100 keV monoenergetic photons was calculated in the nucleus‎. To investigate the effect of the approach used for distribution of GNPs in the medium on dose enhancement factor‎ (‎DEF)‎, three models have been proposed‎: ‎filling the medium and the cytoplasm with either a gold-water mixture or a homogeneously distributed GNPs‎, ‎and the heterogeneous model by simulating spheres of GNPs localized in the cytoplasm‎. ResultsThe results show an overestimation of dose enhancement caused by gold-water mixture rather than that of homogeneous distribution‎. The DEFs for the heterogeneous model‎, ‎while follow the same behavior of two other models against various primary energies‎, ‎quantitatively demonstrate a significant distinction‎. ‎This model was also examined by studying the effect of concentration (the ratio of the mass of GNPs to the mass of the medium)‎, ‎size and density of‎ GNPs on nucleus dose enhancement‎. ‎It was found that though the values calculated for DEF strongly depend on concentration of GNPs‎, ‎for a given concentration‎, ‎they would not considerably be affected by changing the GNPs' size‎. As a criterion to assess their density around the nucleus‎, ‎the distance between two typical GNPs was found to be a key determinant factor to predict and to control dose enhancement in the target volume‎. For the primary photons of 30 keV‎, ‎our results showed a negligible difference between the DEFs calculated due to the cell orientation in the medium‎. ‎By extending the heterogeneous model for ten different locations of nucleus in the cell‎, ‎the energy dependence behavior of DEF was observed‎. ConclusionsThe results obtained emphasize the importance of accurate modeling of the distribution of GNPs in cell to demonstrate the more precise potential of gold in improving radiotherapy treatments‎.

Effect of royal jelly on longevity and memory-related traits of Apis mellifera workers

Abstract Royal jelly (RJ) is a key factor for honey bee caste determination. The queen bee is fed with RJ by worker bees throughout her life, while the worker bees eat bee bread themselves. This study was designed to explore the effect of nutrient-rich RJ on longevity and learning and memory abilities of workers of the western honey bee Apis mellifera. The newly emerged worker bees were randomly divided into three groups and were fed 50% sucrose solution containing 0%, 10%, and 20% RJ. We found that worker bees fed with 10% and 20% RJ showed significantly improved longevity and higher proboscis extension response success rate compared to bees fed with 50% sucrose containing 0% RJ. Additionally, bees fed with 20% RJ showed significantly higher level of expression of memory related genes (GluRA and Nmdar1) compared to the control group. Furthermore, expression of the Nmdar1 gene of worker bees fed with 10% RJ was also significantly higher than in the control group. These results indicate that RJ has potential effects on the longevity and learning and memory abilities of A. mellifera.

Ectopic Fat Accumulation in Distinct Insulin Resistant Phenotypes; Targets for Personalized Nutritional Interventions.

Cardiometabolic diseases are one of the leading causes for disability and mortality in the Western world. The prevalence of these chronic diseases is expected to rise even further in the next decades. Insulin resistance (IR) and related metabolic disturbances are linked to ectopic fat deposition, which is the storage of excess lipids in metabolic organs such as liver and muscle. Notably, a vicious circle exists between IR and ectopic fat, together increasing the risk for the development of cardiometabolic diseases. Nutrition is a key-determining factor for both IR and ectopic fat deposition. The macronutrient composition of the diet may impact metabolic processes related to ectopic fat accumulation and IR. Interestingly, however, the metabolic phenotype of an individual may determine the response to a certain diet. Therefore, population-based nutritional interventions may not always lead to the most optimal (cardiometabolic) outcomes at the individual level, and differences in the metabolic phenotype may underlie conflicting findings related to IR and ectopic fat in dietary intervention studies. Detailed metabolic phenotyping will help to better understand the complex relationship between diet and metabolic regulation, and to optimize intervention outcomes. A subgroup-based approach that integrates, among others, tissue-specific IR, cardiometabolic parameters, anthropometrics, gut microbiota, age, sex, ethnicity, and psychological factors may thereby increase the efficacy of dietary interventions. Nevertheless, the implementation of more personalized nutrition may be complex, costly, and time consuming. Future studies are urgently warranted to obtain insight into a more personalized approach to nutritional interventions, taking into account the metabolic phenotype to ultimately improve insulin sensitivity and reduce the risk for cardiometabolic diseases.

Access to Subsidised Packing Credit for Financing Export: Who are the Gainers?

This study examines the packing credit or pre-shipment credit (PC) as a key determinant factor for the export growth in India. PC is considered to be an important means of financing export if advance payment is not received by the exporter prior to the shipment of goods. The Government of India’s (GoI) scheme of interest subsidy in PC is mostly to boost the export growth in India. In this backdrop, this article is having threefold objectives: (a) to examine the distribution pattern of PC across various exporting sectors; (b) to analyse the availability of export financing at different interest rate range; and (c) to estimate the sensitivity of export growth of India to its utilisation of PC in small, medium and large exporting sectors. Our preliminary analysis reveals that natural elimination takes place, and the present practice of disbursing PC is not able to fulfil the goal of establishing a level playing field for the exporters. Per capita utilisation of PC shows highly skewed preference of the banks to large borrowers, even if they are not subject to the benefit of interest subvention. This study also reveals that small exporters hold the maximum number of PC account, although having the least outstanding amount per account. On the contrary, our Arellano–Bond Dynamic panel analysis for the period 1996–1997 to 2015–2016 shows that the utilisation of PC by medium and small exporters respectively are more sensitive to boost the export growth of India. This study also finds that the effect of the interest subvention scheme was dampened due to the financial crisis and concludes that the export growth would have been much worse affected in the absence of the subvention scheme. Our empirical examination concludes that interest subvention plays a positive and significant role to boost the export growth and additional reduction in the cost of production may add to the export growth of India. This study recommends that the government may introduce a differential interest subsidy for different creditworthy exporters within the entitled sectors to reduce the cost of fund effectively for more needy and sensitive exporters. Given the resource constraint, it may be ensured that large exporters are restricted from receiving the subsidised export finance. JEL: F49, F30, G01, G18, G32

Impacts of oil price shocks on the United States economy: A meta-analysis of the oil price elasticity of GDP for net oil-importing economies

Policy makers are interested in estimates of the potential economic impacts of oil price shocks, particularly during periods of rapid and large increases that accompany severe supply shocks. Literature estimates of the economic impacts of oil price shocks, summarized by the oil price elasticity of GDP, span a very wide range due to both fundamental economic and methodological factors. This paper presents a quantitative meta-analysis of the oil price elasticity of GDP for net oil importing countries, with a focus on the United States (US). The full range of estimates of the oil price elasticity of GDP for the US in the data is − 0.124 to + 0.017, accounting for different methodologies, data and other factors. We employ a meta-regression model that controls for key determinant factors to estimate the mean and variance of the GDP elasticity across studies. We use a robust estimation technique to deal with heterogeneity of the data and well-known econometric issues that confront meta-analysis. The resulting regression model is used to simulate the oil price elasticity of GDP for the US, with a mean of − 0.020% and 68% confidence interval of − 0.035 to − 0.006, four quarters after a shock.

Groundwater markets in east coast of Puducherry Union Territorry: analysis of pricing and irrigation efficiency

This paper examines structure, determinants and efficiency of groundwater markets and suggest policy measures to contain over-extraction of groundwater in the Union territory of Puducherry on east coast of India. The analysis of structure of groundwater market shows a large proportion (82%) of the farmers entering into one or the other activities related to water market. The number of water buyers decreases with increase in farm size, while the number of sellers increases with the increase in farm size. The analysis of conduct of groundwater markets reveals a seller-buyer concentration ratio of 1: 2.39. The farmers having less operational landholdings, higher fragmented landholdings and low capacity water lifting device have a higher probability of buying groundwater. Further, selling of groundwater is more concentrated among farmers with large operational holdings, less fragmentation and joint ownership of a modern water extraction mechanism (WEM). Resource use efficiency analysis indicates a close association between increased productivity and better irrigation management due to ownership of the modern WEMs. The Nash equilibrium framework used to study the bargaining power brings out that the level of irrigation of buyers and sellers as key factors in price determination in groundwater market. The selling price of groundwater is found markedly higher than the total cost of water extraction, implying exploitative nature of groundwater markets.

NMR Metabolomics for Stem Cell type discrimination

Cell metabolism is a key determinant factor for the pluripotency and fate commitment of Stem Cells (SCs) during development, ageing, pathological onset and progression. We derived and cultured selected subpopulations of rodent fetal, postnatal, adult Neural SCs (NSCs) and postnatal glial progenitors, Olfactory Ensheathing Cells (OECs), respectively from the subventricular zone (SVZ) and the olfactory bulb (OB). Cell lysates were analyzed by proton Nuclear Magnetic Resonance (1H-NMR) spectroscopy leading to metabolites identification and quantitation. Subsequent multivariate analysis of NMR data by Principal Component Analysis (PCA), and Partial Least Square Discriminant Analysis (PLS-DA) allowed data reduction and cluster analysis. This strategy ensures the definition of specific features in the metabolic content of phenotypically similar SCs sharing a common developmental origin. The metabolic fingerprints for selective metabolites or for the whole spectra demonstrated enhanced peculiarities among cell types. The key result of our work is a neat divergence between OECs and the remaining NSC cells. We also show that statistically significant differences for selective metabolites characterizes NSCs of different ages. Finally, the retrived metabolome in cell cultures correlates to the physiological SC features, thus allowing an integrated bioengineering approach for biologic fingerprints able to dissect the (neural) SC molecular specificities.

Early microbiota, antibiotics and health.

The colonization of the neonatal digestive tract provides a microbial stimulus required for an adequate maturation towards the physiological homeostasis of the host. This colonization, which is affected by several factors, begins with facultative anaerobes and continues with anaerobic genera. Accumulating evidence underlines the key role of the early neonatal period for this microbiota-induced maturation, being a key determinant factor for later health. Therefore, understanding the factors that determine the establishment of the microbiota in the infant is of critical importance. Exposure to antibiotics, either prenatally or postnatally, is common in early life mainly due to the use of intrapartum prophylaxis or to the administration of antibiotics in C-section deliveries. However, we are still far from understanding the impact of early antibiotics and their long-term effects. Increased risk of non-communicable diseases, such as allergies or obesity, has been observed in individuals exposed to antibiotics during early infancy. Moreover, the impact of antibiotics on the establishment of the infant gut resistome, and on the role of the microbiota as a reservoir of resistance genes, should be evaluated in the context of the problems associated with the increasing number of antibiotic resistant pathogenic strains. In this article, we review and discuss the above-mentioned issues with the aim of encouraging debate on the actions needed for understanding the impact of early life antibiotics upon human microbiota and health and for developing strategies aimed at minimizing this impact.

The ubiquitin ligase SCFFBXW7α promotes GATA3 degradation.

GATA3 is a key transcription factor in cell fate determination and its dysregulation has been implicated in various types of malignancies. However, how the abundance and function of GATA3 are regulated remains unclear. Here, we report that GATA3 is physically associated with FBXW7α, and FBXW7α destabilizes GATA3 through assembly of a SKP1-CUL1-F-box E3 ligase complex. Importantly, we showed that FBXW7α promotes GATA3 ubiquitination and degradation in a GSK3 dependent manner. Furthermore, we demonstrated that FBXW7α inhibits breast cancer cells survival through destabilizing GATA3, and the expression level of FBXW7α is negatively correlated with that of GATA3 in breast cancer samples. This study indicated that FBXW7α is a critical negative regulator of GATA3 and revealed a pathway for the maintenance of GATA3 abundance in breast cancer cells.

Effects of Incubation Temperature on the Expression of Sex-Related Genes in the Chinese Pond Turtle, Mauremys reevesii

Despite widespread temperature-dependent sex determination (TSD) in reptiles, it is still unclear how the molecular network responds to temperature variation and drives the sexual fate. Profiling of sex-related genes is the first step in understanding the sex determination system in reptiles. In this study, we cloned the full-length coding sequences of Cyp19a1, Foxl2, Rspo1, Sf1, and Sox9 in an Asian freshwater turtle (Mauremys reevesii) with TSD and identified the expression patterns of these genes and Dmrt1 at different incubation temperatures to understand their roles in urogenital development. Our results showed that Cyp19a1, Foxl2, and Rspo1 were expressed in the adrenal-kidney-gonadal complex at a high level in females, while Sf1 and Dmrt1 were highly expressed in males. In addition, Foxl2 and Rspo1 showed sex-dimorphic expression in the presumed early thermosensitive period (TSP), Dmrt1 was upregulated at the beginning of the presumed TSP, and Sox9 did not show sex-dimorphic expression until the end of the presumed TSP. These results suggest that Foxl2 and Rspo1 are probably upstream genes involved in female sex determination and that Dmrt1 may be a key factor in male sex determination. Therefore, our study provides a solid foundation for further investigations on the molecular mechanism underlying sex determination in M. reevesii.

Computer-aided Preoperative Pulmonary Segment Analysis for Segmentectomy Based on CT Images

We proposed a preoperative analysis of pulmonary segment for safer segmentectomy. With image processing functions including serial lung CT image segmentation and vessel extraction, a three-dimensional interactive lung model is reconstructed for further pulmonary segment analysis. By human-computer interaction, it is able to obtain vascular territory information which provides the key factor for determination of pulmonary segments and volumetric assessment of each segment. The result shows a promising application of preoperative pulmonary segment analysis in lung surgeries.

A resource-based view of utilities: The key-determinant factors for customer prices and organizational costs in the Portuguese water industry

The resource-based view supports the idea that firms that make better use of their existing resources have superior performance, which depends on organizational processes and routines to lower organizational costs and prices to customers. By applying this approach to the Portuguese water industry based on a cross-sectional research strategy, the findings demonstrate that public firms' with lower organizational costs are able to charge lower prices. There are two implications of the current findings. The first is political in nature and involves the discussion of the best way to improve the provision of public services by utilities. From an economic, managerial and social approach, all the arrangements, whether public or private, should be rethought. The second implication is theoretical, since firm effects can be established based on the existence of superior resources, the key variable to explain differences in organizational performance.

DACH1 suppresses breast cancer as a negative regulator of CD44

Dachshund homolog 1 (DACH1), a key cell fate determination factor, contributes to tumorigenesis, invasion, metastasis of human breast neoplasm. However, the exact molecular mechanisms for the anti-tumor roles of DACH1 in breast carcinoma are still lack of extensive understanding. Herein, we utilized immunohistochemistry (IHC) staining and public microarray data analysis showing that DACH1 was higher in normal breast, low-grade and luminal-type cancer in comparison with breast carcinoma, high-grade and basal-like tumors respectively. Additionally, both correlation analysis of public databases of human breast carcinoma and IHC analysis of mice xenograft tumors demonstrated that DACH1 inversely related to cancer stem cells (CSCs) markers, epithelial-mesenchymal transition (EMT) inducers and basal-enriched molecules, while cluster of differentiation 44 (CD44) behaved in an opposite manner. Furthermore, mice transplanted tumor model indicated that breast cancer cells Met-1 with up-regulation of DACH1 were endowed with remarkably reduced potential of tumorigenesis. Importantly, meta-analysis of 19 Gene Expression Omnibus (GEO) databases of breast cancer implicated that patients with higher DACH1 expression had prolonged time to death, recurrence and metastasis, while CD44 was a promising biomarker predicting worse overall survival (OS) and metastasis-free survival (MFS). Collectively, our study indicated that CD44 might be a novel target of DACH1 in breast carcinoma.

From pioneering orientation to new product performance through competitive tactics in SMEs

The literature regarding entry timing suggests that pioneering orientation (PO) is a key determinant factor of new product performance (NPP) due to ‘first mover advantages’. The contradictory results and specific biases raise a research gap on which conditions and processes lead PO to a higher NPP. This paper proposes to fill this gap by designing and testing a model examining to what extent development of competitive tactics drive and explain the way from PO to NPP. We test the model on a sample of 224 footwear firms. Results show that, separately, each of the competitive tactics has a total mediating effect linking PO with NPP. Introducing the competitive tactics into a multiple mediator model the routes from PO to NPP through low cost and innovation differentiation are relevant and compatible. However, marketing differentiation is less effective. The study provides new ways of linking the entry timing and advantage strategy perspectives.

Male post-prostatectomy incontinence MDT

The management of post-prostatectomy incontinence remains controversial with ongoing confusion as to who benefits from male sling or artificial urinary sphincter. We present a post-prostatectomy incontinence MDT format to illustrate key factors in decision-making and determination of best management in post-prostatectomy incontinence.

Assessing the Determinants of Cloud Computing Services for Utilizing Health Information Systems: A Case Study

Health information systems refer to the utilization of IT-related systems to capture, store, manage, or transmit information related to the health of individuals or the activities within the health sector. Utilizing cloud services in the healthcare sector is a flexible solution to improve the performance of an organization as it can provide numerous features such as self-service, ubiquitous network access, resource pooling, rapid elasticity, and pay-per-use pattern. A preliminary study was conducted in the Iraqi public healthcare sector to obtain preliminary data acquisition about the current situation of IT and to determine the key factors associated with the utilization of cloud computing to foster current health information systems. During the study, a total of 30 technicians and physicians from four hospitals in Iraq were invited for interview in which the researcher directed questions in a semi-structured form. The findings of the investigation concluded the key determinant factors; these include factors related to the environmental structure such as software, hardware, cost, network, and training. Other factors that were found related to the system such as compatibility, complexity, data security and privacy. These two aspects were found to influence personal factors related to the behavioural control and confirmation to utilize cloud computing services in this sector.

A new quality factor for the building stone industry: a case study of stone blocks, slabs, and tiles

In building stones, discontinuities, non-uniformity, and irregular shape are among the problems that reduce the quality of products. Stone blocks, slabs, and tiles are the main products of quarries and stone processing plants. Quantifying the quality is a key factor in valuation of these products. This paper proposes a quality factor formula to determine the quality of stone blocks (three-dimensional) and products from stone processing plants (two-dimensional). This factor, which shows the uniformity and esthetic index of a piece of stone, is determined based on the shape quality (α), number, size, and esthetic quality (β) of the pieces and the discontinuity factor (γ) that separates the pieces. The quality factor is defined in a way that each previously mentioned characteristic of a piece is involved in the quality factor formula calculation. The quality factor ranges between 0 and 1 and can be expressed as a percentage. The proposed quality factor was calculated for a number of different stone blocks, slabs, and tiles to examine the validity of the quality factor formula. The results showed that the shape quality is the most significant parameter in determining the quality of stone blocks in quarries. Moreover, in processing plant products the esthetic quality and the number of stone pieces in a product are the key factors for determination of their quality. The discontinuity factor is a parameter that reduces the quality of stone products significantly. Furthermore, the quality factor formula can be used as a convenient tool for classifying the products of quarries and stone processing plants.

Embarazo ectópico abdominal avanzado: reporte de casos y revisión de la literatura

Objetivo: el objetivo de este estudio es reportar dos casos de embarazo ectópico abdominal avanzado, con buen resultado materno / perinatal, y revisar la literatura disponible con respecto al manejo de la placenta y el pronóstico de esta entidad.Materiales y métodos: se describen dos casos de embarazo ectópico abdominal avanzado en los que se realizó extracción de la placenta, con feto viable y resultado perinatal favorable. Estos fueron atendidos en una institución de cuarto nivel de complejidad, ubicada en la ciudad de Cali, Colombia. Se realizó una revisión de la literatura registrada en las bases de datos Medline vía PubMed, con los términos de búsqueda: “embarazo abdominal”, “embarazo esplénico”, “embarazo hepático”, “embarazo omental” y “embarazo peritoneal”. La búsqueda se limitó a artículos publicados durante los últimos doce años en inglés y español.Resultados: se recuperaron 228 referencias, de las cuales 42 artículos cumplieron con los criterios de inclusión que informan un total de 74 pacientes con embarazo ectópico abdominal. En cuanto al manejo de la placenta, la remoción de la misma se informó en 42 casos (58%). La mortalidad materna se presentó en 4 casos (4,1%), todos por hemorragia posparto. Un total de 60 pacientes (81%) presentaron complicaciones, la más frecuente fue hemorragia en 38 de ellas (51%). En cuanto al resultado perinatal, se encontró una mortalidad perinatal del (43,8%).Conclusión: el manejo de la placenta es el punto clave del que podría depender la frecuencia de complicaciones maternas. Se requieren estudios prospectivos que evalúen el manejo más seguro y efectivo de esta condición.

Grafting Binary PEG and Fluoropolymer Brushes from Mix-Biomimic Initiator as “Ambiguous” Surfaces for Antibiofouling

A series of random binary poly(ethylene glycol) and fluoropolymer brushes (POEGMA-PNCA-F15) are grafted onto substrates via surface-initiated polymerizations (atomic transfer radical polymerization and ring opening metathesis polymerization, respectively) from polydopamine based mix-catecholic initiators. The chemical composition, surface morphology, swellability, and wettability of the as-prepared surfaces are characterized by X-ray photoelectron spectra (XPS), atomic force microscopy (AFM), and static water contact angle measurements, respectively. The antifouling properties are evaluated by settlement of spores and diatoms, the results indicate that the as-prepared amphiphilic surfaces with random hydrophilic and hydrophobic polymer brushes can mitigate biofouling, and the ratio of the hydrophilic and hydrophobic polymer brushes is a key determinant factor in antifouling effect, the optimal ratio (1:1 initiator) of bipolymer brushes on surfaces exhibits good antiadhesion performance against both Chlorella spores and Navicula diatoms.

Spatial Heterogeneity of Energy-Related CO2 Emission Growth Rates around the World and Their Determinants during 1990–2014

Understanding the spatial heterogeneity and driving force identification of energy-related CO2 emissions (ECEs) can help build consensus for mitigating CO2 emissions and designing appropriate policies. However, previous studies on ECEs that focus on both the global-regional scale and the interaction of factors have been seldom conducted. In this paper, ECE data from 143 countries from 1990 to 2014 were selected to analyze regional differences in ECE growth rates by using the coefficient of variation. Then a geographical detector was used to analyze the key determinant factors on ECE growth rates around the world and in eight types of regions. The results show that: (1) the ECE growth rate in the Organization for Economic Cooperation and Development (OECD) region is low and tended to decrease, while in the non-OECD region it is high and tended to increase; (2) the coefficient of variation and detection factor of ECE growth rates at a regional scale are higher than those at a global scale; (3) in terms of the key determinant factors, population growth rate, growth rate of per capita GDP, and energy intensity growth rate are the three key determinant factors of ECE growth rates in the OECD region and most of the non-OECD regions such as non-OECD European and Eurasian (NO-EE), Asia (NO-AS), non-OECD Americas (NO-AM). The key determinant factors in the African (NO-AF) region are population growth rates and natural gas carbon intensity growth rates. The key determinant factors of the Middle East (NO-ME) are population growth rate, coal carbon intensity growth rate and per capita GDP growth rate; (4) the determinant power of the detection factor, the population growth rate at the global scale and regional scale is the strongest, showing a significant spatial consistency. The determinant power of per capita GDP growth rate and energy intensity growth rate in the OECD region, respectively, rank second and third, also showing a spatial consistency. However, the carbon intensity growth rates of the three fossil fuels contribute little to the growth rate of ECEs, and their spatial coherence is weak; (5) from the perspective of the interaction of detection factors, six detection factors showed bilinear or non-linear enhancement at a global and a regional scale, and the determinant power of the interaction of factors was significantly enhanced; and (6) from the perspective of ecological detection, the growth rate of carbon intensity and the growth rate of natural gas carbon intensity at the global scale and NO-ME region are significantly stronger than other factors, with a significant difference in the spatial distribution of its incidence. Therefore, the OECD region should continue to reduce the growth of energy intensity, and develop alternative energy resources in the future, while those that are plagued by carbon emissions in non-OECD regions should pay more attention to the positive influence of lower population growth rates on reducing the growth rate of energy-related CO2 emissions. Reducing energy intensity growth rates and reducing, fossil energy consumption carbon intensity.