Além dos investimentos públicos para promoção, proteção e apoio ao AM em FSA, é possível que mudanças de algumas características da população tenham influenciado os indicadores de AM. Comparando as variáveis maternas e das crianças nas duas últimas pesquisas, constataram‐se algumas mudanças que podem favorecer ou dificultar o avanço nos indicadores do AM. Dentre os fatores maternos que podem contribuir positivamente estão Phenyl sulfate menor proporção de mães adolescentes e a melhoria da escolaridade. Embora não haja consenso quanto à associação entre menor idade materna e menores índices de AM, estudos mostram essa associação no Brasil. Da mesma maneira, a maioria dos estudos relata associação positiva entre maior escolaridade materna e duração do AM, sobretudo a do AME, com efeito dose‐resposta.
Quanto às características das crianças, a diminuição na prevalência do uso de chupeta provavelmente está associada com a evolução positiva dos indicadores de AM em FSA. A associação entre uso de chupeta e duração do AM tem sido demonstrada em praticamente todos os estudos. Entretanto, é importante enfatizar que ainda não estão esclarecidos os mecanismos envolvidos. Uma metanálise recente sugere que o uso de chupeta por filhos de mulheres altamente motivadas para amamentar não esteve associado com menor duração do AM, independentemente da idade em que a chupeta foi iniciada.
Assim como algumas mudanças nas características da população podem ter favorecido a evolução positiva dos indicadores de AM no município, outras podem ter inibido um avanço maior, como o acréscimo na proporção de mães primíparas e de partos cesáreos. Apesar de as mulheres primíparas desejarem iniciar a amamentação, costumam praticá‐la por menor tempo. Quanto ao tipo de parto, estudos constataram menor prevalência de AM e AME em mulheres submetidas a partos cirúrgicos. Feira de Santana segue a tendência nacional de aumento da prevalência de parto cesáreo no Brasil.
Além dos fatores individuais já mencionados, a redução de nascimentos em HAC pode ter influenciado negativamente a Crossover fixtion evolução dos indicadores de AM, pois está bem documentada a influência positiva da IHAC nas prevalências de AM.
A principal limitação metodológica deste estudo deve‐se ao seu delineamento, o qual não permite estabelecer uma perfeita vinculação causal entre as mudanças das características da população e a evolução do AM, por se tratar de um inquérito transversal. Além disso, não foram pesquisadas algumas características sociodemográficas, tais como renda familiar, informações do pré‐natal e variáveis paternas, entre outras; além da ausência de informação sobre o indicador AM na primeira hora de vida e das características da população no inquérito feito em 1996. Por outro lado, a abordagem metodológica usada é factível e reproduzível, o que possibilita o monitoramento dos indicadores de AM ao longo do tempo, tão importante para o planejamento de ações no nível local.
Conflitos de interesse
A hipertensão arterial sistêmica (HAS) é um importante fator de risco para eventos mórbidos cardiovasculares. É encontrada predominantemente em adultos e idosos. Entretanto, sua prevalência vem aumentando na faixa etária pediátrica, devido principalmente a modificações no estilo de vida.
Apesar da importância de tal condição, a HAS na infância é pouco diagnosticada. Vários fatores colaboram para tal, porém o processo diagnóstico é apontado como um dos principais. Ele envolve a análise de várias tabelas de percentis, pois a pressão arterial (PA) na faixa etária pediátrica varia de acordo com a idade, gênero e altura.
Diversos métodos foram descritos para simplificar o diagnóstico de HAS em crianças e adolescentes. Alguns deles envolvem a adoção de fórmulas matemáticas, outros usam tabelas simplificadas e o mais recente usa pontos de corte a partir da relação entre PA e altura. A comparação desses métodos entre si pode ser útil na determinação de uma ferramenta de rastreamento adequada para distúrbios da pressão arterial.
Conflitos de interesse
Anomalias congênitas múltiplas afetam de dois a três indivíduos em cada 100 nascidos vivos e são a principal causa de mortalidade e deficiência infantil. Apesar de sua maioria ser isolada e de origem multifatorial, pacientes com anomalias múltiplas precisam de uma avaliação para identificar uma causa genética subjacente.
Nos últimos anos, o estudo etiológico de transtornos no desenvolvimento tem sido enriquecido com o uso clínico de técnicas em microarray. Em países desenvolvidos, o cariótipo molecular, ou a análise cromossômica por microarray (CMA), é considerado a técnica de primeira linha para a análise de pacientes com anomalias congênitas múltiplas, atraso de desenvolvimento/deficiência intelectual não sindrômicos e transtornos do espectro autista.
Em contrapartida, em países em desenvolvimento, como da América Latina, a detecção de anomalias cromossômicas ainda é feita principalmente por técnicas citogenéticas convencionais. O cariótipo com bandamento GTG (banda G pela tripsina e corante giemsa) em linfócitos tem sido amplamente usado principalmente para identificar anomalias cromossômicas com uma resolução maior ou igual a 5‐10 megabases (5‐10 Mb). A hibridização in situ por fluorescência (FISH) está disponível para um número limitado de doenças causadas por microdeleções/microduplicações cromossômicas e tem uma resolução de 2‐5 PHA-793887 em núcleos metafásicos e entre 50‐150 Kb em núcleos interfásicos. Outras técnicas moleculares foram desenvolvidas para procurar pequenas microdeleções/microduplicações, como a Amplificação de Múltiplas Sondas Dependentes de Ligação (MLPA). Em contrapartida a essas técnicas convencionais, a CMA tem maior resolução, que atinge 50 Kb, dez vezes maior do que a resolução do cariótipo convencional. Essa busca desequilíbrios genéticos (ganhos ou perdas de segmentos cromossômicos) em todo o genoma e tem permitido a identificação de novas síndromes não prontamente detectadas pelos métodos descritos anteriormente. A descoberta da variante normal em variantes do número de cópias (CNVs) representa um desafio à interpretação clínica.
Embora os estudos de diagnóstico para indivíduos com anomalias congênitas ou deficiência intelectual com base na citogenética convencional apresentem rendimento diagnóstico próximo de 3%, a CMA apresenta rendimento de aproximadamente 15‐20%, ou seja, mais de cinco vezes acima do cariótipo com bandamento G, o que justifica seu uso como teste de diagnóstico de primeira linha para pacientes com diagnósticos clínicos desconhecidos. Estima‐se que a CMA consiga detectar, individualmente, mais de 99% de todas as anomalias do cariótipo.
Dos 40 pacientes analisados, 16 (41%) eram do sexo feminino. As idades variavam de um mês a 25 anos, com uma idade média de 4,2 anos. Como selecionado, a vasta maioria de nossos pacientes tem anomalias múltiplas, incluindo transtornos de desenvolvimento estruturais e funcionais. Os detalhes clínicos estão resumidos na tabela 1.
Este é o primeiro relatório de teste de CMA em uma coorte de pacientes chilenos com deficiências de desenvolvimento, considerando que existem poucos relatórios do uso clínico de microarrays cromossômicos na América Latina, que relatam experiências de casos individuais. Na América do Sul, uma experiência semelhante foi relatada em um grupo de pacientes no Brasil. Foram analisados 95 pacientes “sindrômicos”’ com cariótipo normal e foi relatado um rendimento diagnóstico de 17%.
Detectamos mais de 25% de alterações patogênicas em nossa coorte, que estão na mais alta faixa relatada na literatura. Em pacientes com atraso de desenvolvimento/deficiência intelectual sindrômicos e não sindrômicos e cariótipo normal/Fish, a metanálise apresenta um rendimento diagnóstico de 7,8%‐13,8%, variação de 5% a 50%. Isso é explicado, em grande parte, pela heterogeneidade no modelo dos estudos, principalmente na seleção dos pacientes, testes previamente feitos e plataforma de array usada. Em nosso caso, a alta taxa de diagnóstico pode ser explicada pelo fato de que a coorte estudada é relativamente pequena e apresenta o viés de pacientes muito bem selecionados, muitos dos quais permaneceram sem diagnóstico por muito tempo. Finalmente, usamos uma plataforma de alta densidade.
It is supposed that in mammals the ASG is known to have a variety of bioactive molecules . These molecules exert a wide-ranging effect on female reproductive activities. A portion of ASG proteins make a nutritional contribution in spermatozoa and they also exert an influence on spermatozoa vitality [35,36] and aa-utp capacity [13,37], and can induced a cascade of membrane alterations . We presume that the AG secretion of P. plicatum may also have the aforementioned functions, which warrants more research.
In conclusion, the AG is an important component of the male reproductive system in crabs, which functions to enhance the fertility of spermatozoa, digest the spermatophore wall, provide nutrition to the spermatozoa, and is involved in antibacterial activity and spermatozoal viability. Surveying the presence of AG among the brachyuran crabs, it becomes apparent that the AG is present in several of the mangrove and estuarine crabs: Grapsidae, Majidae, and Ocypodidae crabs (M. messor, S. quadratum, O. ceraptothalmus, M. brachydactyla, and E. sinensis). This suggests an additional adaptive role in their respective ecosystems and phylogenic significance, although AG materials are an independent and important component of the male reproductive system of brachyuran crabs that warrants further research in all taxa.
Conflict of interest
Results and discussion
Mg–1.5Zn–0.6Zr–0∼4Er magnesium alloys were extruded at 350 °C and 420 °C to obtain microstructures with different dynamic recrystallization (DRX) degree and then undergone annealing treatment in the temperature range of 250–400 °C for a fixed time of 1.5 h. The effects of Er addition and its existing form on the static recrystallization and grain growth during annealing were studied. The results showed that for the incomplete DRX microstructures extruded at a lower temperature of 350 °C, the critical static recrystallization temperature increased with the increase of Er addition, the temperature range being 315–335 °C for alloys with lower Er addition and shifting to a higher temperature range of 350–365 °C for an increased Er content of 2%. Er addition increased the resistance of static recrystallization. For the complete DRX microstructures extruded at a relatively high temperature of 420 °C, Er addition suppressed grain growth. The activation energy for grain boundary motion for Er-free alloy was calculated to be 23.8 kJ mol−1. A remarkable increase in activation energy was obtained in the 2% Er-containing alloy, being as high as 93.5 kJ mol−1. The 2% Er-containing alloy manifested the best thermal stability. Both the intermetallic phase and the solute atoms of Er in α-Mg matrix contributed to the microstructure stability. Moreover, it is believed that the existing form of Er–Zn Autophagy Compound Library pairs in the α-Mg solid solution favored the most to improve the thermal stability of the alloy.
The authors are grateful for the financial support of the National Natural Science Foundation of China (No. 51271207) and sharing fund of Chongqing University\’s large-scale equipment.
In recent years, semi-solid metal (SSM) processing has been recognized as a potential process in light alloy forming, due to its unique advantages over conventional casting processes, such as near net shape forming, improved mechanical properties, low porosity and long die life. Generally, SSM processing can be divided into two routes, i.e. rheoforming and thixoforming. The distinct difference between rheoforming and thixoforming is that, semi-solid slurry used in rheoforming is partially solidified from the liquid state, while that used in thixoforming is partially melted from the solid state. For both rheoforming and thixoforming, the key requirement is the thixotropic slurry with non-dendritic primary particles uniformly distributed in the liquid matrix. It is well accepted that, the finer and rounder the primary particles, the better the rheology of semisolid slurry and the resulting mechanical properties [1–3].
Thixoforming involves the reheating of feedstock materials into semi-solid state . In order to get non-dendritic microstructure via reheating, feedstock materials are always prepared by some special techniques, such as electromagnetic stirring [5,6], spray casting  and strain induced melt activation (SIMA) [8,9]. But these techniques will also introduce extra cost. Semi-solid isothermal heat treatment is a relatively simple method invented in the 1990s , which is able to produce non-dendritic slurries without any special procedures. So it is a promising technique for practical application of thixoforming.
Until now, magnesium alloys studied and used in SSM processing are limited to commercial Mg–Al alloys such as AZ91, AM60 and AM50 [11–13], the application is then restricted by their inherent deficiencies, such as poor high temperature strength and creep resistance . Rare earth metals (RE) have been demonstrated the most effective elements to improve the strength of Mg alloys especially at elevated temperature. It has been reported that the recently developed Mg–Gd–Y–Zr magnesium alloys showed considerable precipitation hardening, therefore exhibited higher specific strength at both room and elevated temperature and better creep resistance than conventional aluminium and magnesium alloys, including WE54 and QE22 [15–17]. The thixoformability of Mg–Gd–Y–Zr alloy has also been calculated quantitatively in previous work . Recently, several works have focused on the SIMA route of Mg–Gd–Y–Zr alloy [19,20].
The level of education of asthmatic individuals and their ability to understand the instructions given are crucial to the adequate control of the disease. Watson et al. divided 398 children who frequently visited emergency rooms for apelin receptor attacks into two groups, one with the usual instructions received from the doctors and another with the educational intervention of an interactive program without modifying their medication. Using educational material alone, the authors were able to reduce emergency visits by 38%. The results from the present study have shown an inverse correlation between admissions due to asthma and the education dimension of the FIMD, corroborating the aforementioned study. Bacon et al. investigated the relationship between asthma and socioeconomic factors in 781 asthmatic adults and concluded that a higher prevalence of unhealthy behaviors among asthmatic adults with a low level of education may in part explain such a strong relationship. Many authors corroborate this finding.
Further insight into the socioeconomic universe showed that recent studies suggest a coherent relationship between community violence and asthma prevalence and severity. Community violence is herein defined as a sensation of being unsafe as a result of several negative factors that disturb the harmony and social living, such as crime, exposure to illegal drugs, poverty, unemployment and inequality. The dimensions that compose the IYVV measure these exact factors and are more suitable to detect levels of community violence than trauma or individual victimization.
The descriptive analysis of the data in this study revealed that the Brazilian regions with the highest average IYVV scores were the North, Northeast and Central-West for almost all dimensions. The same regions presented the highest rates of hospital admissions due to asthma. The dimensions of road traffic accidents and inequality were the only variables in which the South and Southeast regions were at the same level as the others. They were, however, also the only two dimensions that did not correlate with asthma. Bivariate analysis revealed a direct relationship between IYVV and municipal hospital admissions due to asthma. These data indicate that the towns most exposed to community violence have a lower control of asthma and, consequently higher hospital admissions. An R2 of 0.058 indicates that up to 5.8% of the increase in hospitalizations may be due to a concomitant increase in the IYVV, which is in agreement with other studies. Swahn and Bossarte studied 15,214 high-school students in the USA and demonstrated, via interviews, that those who felt unsafe even within the school or en route to or from school had a significantly higher prevalence and poorly controlled asthma.
The main hypotheses that could explain the relationship between community violence and asthma agree that this type of disharmonic sensation caused by surrounding violence is a source of psychological stress and, as such has a direct impact on the immune system and lung function. This could vary from an imbalance between oxidant and antioxidant agents, to the activation of the hypothalamic-pituitary-adrenal axis with cortisol release. In fact, Suglia et al. observed in a prospective study with 43 children that higher symptoms of stress related to community violence predicted higher levels of salivary cortisol.
Regarding the school and job absence dimension of the IYVV, the direct correlation with asthma found in this study was within the expected, as per previously discussed under the education dimension of the FIMD. The basic difference is that for the IYVV, the value is generated from the number of truant children and unemployed adults, as opposed to municipal investments in education. The lack of schools is intimately related to a higher rate of illegal drug use, which is one of the components of community stressors already described as being related to uncontrolled asthma. The unemployment generate a psychological stress; if it is also associated to higher rates of depression, it leads to a negative impact on disease control.
Temporal correlation between reactive astrocytes and itch–scratch cycle
A clinically important element of chronic itch is the vicious tgf beta receptor 1 of itching and scratching. In CV-NC/Nga mice, scratching behavior is induced at the age of 4 weeks, but skin lesions due to scratching are only observed from approximately 8 weeks of age. It is thus conceivable that the itch–scratch cycle might also be established around this time in CV-NC/Nga mice. Interestingly, GFAP upregulation in the SDH is observed only between the ages of 8 and 15 weeks, much later than 4 weeks. Thus it appears that the time course of the appearance of reactive astrocytes matches that of the initiation of the itch–scratch cycle. Furthermore, preventing scratch-induced skin damage by trimming the toenails of CV-NC/Nga mice leads to a recovery from their skin lesions and attenuates GFAP upregulation, as well as reductions in scratching. Similar results were obtained in a model of contact dermatitis. Furthermore, protecting mice from scratching by using an Elizabethan collar prevents GFAP upregulation in the SDH. Thus, it seems likely that SDH astrogliosis under chronic itch conditions might be associated with physical and/or chemical stimulation to the skin by scratching or inflammatory factors.
The mechanism underlying the induction of reactive astrocytes remains to be determined, but the segment in the SDH receiving primary afferent neurons connected with the lesion itchy skin matches that having reactive astrocytes, therefore, astrocytic activation might require a signal from the skin. Tominaga et al. have demonstrated that hyperinnervation of primary afferent C-fibers expressing the transient receptor potential cation channel subfamily V member 1 (TRPV1) to the epidermis occurs in lesioned itchy skin of CV-NC/Nga mice. In patients with atopic dermatitis, the density of epidermal nerve fibers is higher in the skin, suggesting that hyperinnervation might be responsible for chronic itch. It was found that ablation of TRPV1-positive primary afferent C-fibers by systemically administering the ultrapotent TRPV1 agonist resiniferatoxin (RTX) suppresses GFAP upregulation. Thus, reactive astrocytes under chronic itch conditions might be maintained by the lesioned skin in a manner that requires TRPV1+ C-fibers. What biologically active substances are released from primary afferent terminals in the SDH and activates astrocytes under chronic itch condition is a major issue for future investigations.
SDH astrocytes are necessary for chronic itch
Recent studies have implicated SDH reactive astrocytes in chronic itch by demonstrating that repetitive scratching behaviors in models of chronic itch requires the transcription factor signal transducer and activator of transcription 3 (STAT3) and the receptor toll-like receptor 4 (TLR4), both of which in the SDH are selectively activated and expressed in reactive astrocytes.
STAT3 is a member of the STAT family of transcription factors, which has been implicated in the astrocytic activation that appears required for chronic itch. Evidence implicating STAT3 came from convergent results of pharmacological and molecular investigations. It was found that the SDH cells activating STAT3 are astrocytes and because acute pharmacological inhibition of spinal cord STAT3 by intrathecal administration of AG490, an inhibitor of the STAT3 activator Janus kinase (JAK), to the cervical spinal segments suppresses GFAP upregulation and scratching behaviors in models of chronic itch. It appears that ongoing STAT3 activation is crucial for maintaining reactive astrocytes and chronic itch. Moreover, a similar reduction was observed in Gfap-cre:Stat3flox/flox mice, in which astrocytic STAT3 is inactivated by an astrocyte-selective Cre recombination. In contrast, these mice have normal, acute itch responses to histamine and chloroquine (non-histaminergic itch). Thus, STAT3-dependent reactive state of astrocytes in the SDH is necessary for the progression and maintenance of chronic itch.
In our study we found a significant correlation between the inflammatory markers (hs-CRP and IL6) and the severity of airflow obstruction (p=0.037 and 0.002 respectively). It is well established now that systemic ketotifen fumarate is present in stable COPD patients and that its intensity is related to the severity of the underlying disease. Moreover, we found that CRP was inversely correlated with the quadriceps strength as measured by the one repetition maximum as well as the exercise capacity as measured by the 6min walk distance P=0.021 and p=0.036) respectively, also we found that IL6 was inversely correlated to quadriceps strength (P=0.008). Our results indicate that systemic inflammation in COPD predisposes to skeletal muscle weakness and exercise intolerance in stable COPD patients. In consistence with our results, Yende et al. in their study on 2273 elderly individuals, where the pulmonary function testing revealed that 12% of them had COPD, found that the degree of airflow obstruction, as measured by the FEV1, was significantly associated with the degree of muscle weakness. They also found that systemic inflammation as measured by the level of IL-6, was more in patients with COPD and was related to airflow obstruction, muscle weakness and exercise intolerance.
Also Broekhuizen et al. studied 102 patients with severe to very severe COPD, nearly 33% of which were on systemic corticosteroids, who were admitted to an inpatient pulmonary rehabilitation center. They found that reduced FEV1 was correlated with increased plasma levels of CRP and IL-6, confirming that the severity of airflow limitation is associated with systemic inflammation. Their results are in concordance with previous results showing that raised CRP levels were associated with diminished muscle strength, reduced exercise endurance, workload, 6min walk distance, and poor health status and quality of life.
Systemic inflammation has been suggested as a possible cause of hypoandrogenemia in male patients with COPD. However, until now, only a weak significant inverse relationship between the circulating levels of IL-6 and bioavailable testosterone has been found in COPD male patients (r=0.33). In the present study we found no significant correlation between the low testosterone and markers of systemic inflammation (hs-CRP and IL-6). Our results are similar to Karadag et al. who studied 103 COPD patients for sex hormone alterations along with inflammatory markers (TNF-α and IL-6). The study group comprised stable COPD patients and patients undergoing a COPD exacerbation. Although sex hormones were lower and circulating IL-6 and TNF-α concentrations were higher in both stable and exacerbation phase COPD groups than controls, there was no correlation between sex hormones and TNF-α or IL-6. Hence, there is no current evidence to support inflammation as a contributor to testosterone deficiency in COPD.
Declaration of interest
Trauma is one of the most common causes of death in the young population (age group between 1 and 45years). Blunt abdominal trauma (BAT) is very common, and the prevalence of intra-abdominal injury following it has been reported to be as high as 12–15%. The mechanisms resulting in BAT were motor vehicle collision (73%), motorcycle collision (7%), auto-pedestrian collision (6%), and fall (6%).
Rapid diagnosis of abdominal injury is an important step in the treatment process to prevent morbidity or mortality in BAT cases. Rapid determination of cases in need of emergency laparotomy is crucial for life saving, especially for those with unstable hemodynamics, the avoidance of unnecessary surgeries with its invasiveness and complications should be considered.
Ultrasonography (US) is the first imaging method for screening patients with blunt abdominal trauma. It can demonstrate variety of post traumatic abdominal organ pathologies including hematomas, contusions, lacerations, and hemoperitoneum.
Clinical examination and focused abdominal ultrasonography comprise the standard initial abdominal evaluation in post trauma patients. Clinical observation following BAT is a common procedure in all hospitals; however, the required period for observation remains controversial, some suggested that 24h is sufficient, while others reported minimum of an 8-h observation as a sufficient time to identify injuries among hemodynamically stable patients.
Discussion of results
Effect of the size of the surcharge loaded area on the dragload
Numerical analyses were conducted on shielded and unshielded piles of different lengths. Through the analyses the effect of the size of the surcharge loaded area on the long term dragload was considered. The thickness of clay layer Hc varies as 5.1m, 18.0m, 36.3m and 48.0m, corresponding to pile length of 4.8m, 17.7m, 36.0m and 47.7m respectively. The diameter of the surcharge loaded area Ds was kept constant at 60m. The ratio Ds/Hc varies from 11.75, 3.32, 1.65 and 1.25. The location of NP, which are corresponding to maximum long term dragload goes down as Ds/Hc decreases to be close to the pile tip. At ratio of Ds/Hc equal to 11.75, the NP is at depth 0.65 of the pile length, while piles with Ds/Hc equal to 1.25 the NP is at depth 0.78 of the pile length, Figs. 11a and 11c.
Fig. 11a indicated that the shielding piles reduced the long term dragload of shielded pile by a value varies between 0.65 and 0.78 of the long term dragload of unshielded pile, for Ds/Hc varying from 1.25 to 11.75. Fig. 11b presents variation of long term dragload per unit length of the pile (Pn/L) versus Ds/Hc. The figure demonstrates that as the ratio of the size of surcharge loaded area to the thickness of clay layer increases, the long term dragload per unit length of the pile increased. In the figure the pile length L is equal to (Hc – 0.3). So the figure indicates that long term dragload on a pile increased as the diameter of the surcharge loaded area surrounding the pile increased. The variation of (Pn/L) versus Ds/Hc indicated a refraction point at Ds/Hc which equal to 3.32. The achieved result is useful for conducting laboratory tests taking into consideration the elimination of the size effect of surcharge loaded area on dragload. Practically, the surcharge loaded area is of limited size, so the dragload imposed on shielded or unshielded piles is function of the ratio Ds/Hc. Figs. 11b and 11c reflect that as the pile length increases the surface area of pile subjected to NSF increases, and consequently the long term dragload increases. On the other hand Terzaghi’s consolidation order GSK J4 implemented in the study assumes that the superimposed stress at any depth below ground surface is equal to the applied surcharge load, since the surcharge loaded area is extending to infinity, which is not practically true. So one anticipated that, as the pile length increases, and the surcharge imposed on ground surface is extending undefinitely, the long term dragload on the pile shall be increased. On the other side, if the size of the surcharge loaded area is decreased, the influence depth of the superimposed surcharge load decreased and consequently the dragload on pile decreased. Therefore, there are two contradictory actions, the pile length and the size of the surcharge loaded area. Fig. 11a presents an envelope of maximum dragload developed on shielded and unshielded piles. The figure indicates that as the pile length increases from 4.8m to 17.7m, the ratio Ds/Hc decreases from 11.75 to 3.32, and the dragload increases from 730kN to 1180kN, for unshielded pile and from 500kN to 620kN for shielded pile. The effect of pile length on the magnitude of dragload is more pronounced than the effect of the size of the surcharge loaded area. Piles of lengths 36m and 47.7m exhibit maximum dragload which is decreases with the increase of pile length for both shielded and unshielded piles. This means that the effect of the size of surcharge loaded area is more pronounced than the effect of pile length. Therefore a surcharge loaded area surrounding the pile of size bigger than 3.32 times the thickness of clay layer may be considered infinite surcharge loaded area.
It is anticipated that a ratio of Ds/Hc of 3.32 or bigger may leads approximately to the same superimposed load and initial excess porewater pressure through clay layer as infinite surcharge loaded area. In this case the dragload on the pile becomes dependent on pile length and independent of the size of surcharge loaded area and the long term effective stress at any point within the clay layer shall be increased by the value of the surcharge load. Ratios of Ds/Hc less than 3.32, the superimposed load and consequently the excess porewater pressure and the long term effective stress at any point within the clay layer shall be dependent on the depth below clay surface and be less than the surcharge load, except near ground surface. As a result of that the displacement of soil with respect to pile decreased as Ds/Hc decreased with a decreasing long term dragload. Therefore, to minimise the long term dragload on a floating pile the surcharge load area should be limited to a minimum possible size.
Integration of distributed generation (DG) can improve reliability, reduce power losses, improve power quality, decrease environmental pollution and diminish the need for network expansions. The protection devices are set to have a coordinated operation to isolate faults with minimum impact on customers. When DG units are connected to a distribution network, the magnitude and direction of fault current will be changed. So, the coordination between the network protection devices may vanish . Autorecloser-fuse miscoordination and relay–relay miscoordination can occur. Size of DG, location of DG, and type of DG (static or rotating machine) influence the share of DG in total fault current. Thus, these factors determine the DG effect on protection system coordination . Directional overcurrent relays (DOCR) form the primary protection of distribution and sub-transmission systems and the secondary protection of transmission systems. The overcurrent relay (OCR) coordination is realized by adjusting the pickup current setting () and the time dial setting (TDS) of OCR for increasing the selectivity and reliability of protective system . Setting of OCRs is difficult, especially in the multi-loop, multi-source networks. Trial and error, topological analysis, and optimization methods are used for OCRs setting .
The possible solutions to the OCR miscoordination problem in power delivery system (PDS) with and without DGs are searched. In case of PDS without DG, the authors in  reported an approach to break all system loops and coordinate the breakpoint for both directions. In [6,7], a linear graph R115777 method was used to determine a set of breakpoints. Furthermore, optimization approaches such as dual simplex [8,9] and genetic algorithms  were used to minimize the relay operating times. To provide coordination between OCRs under the presence of DG, various techniques are proposed . Ref.  discussed the high-impedance protection applications for tripping acceleration. But this method depends on current transformer (CT) whose dynamic behavior influences the protection stability. Ref.  proposes utilizing the distribution automation system capabilities for protection coordination. One drawback of this method is that the number of protection zones increases when the number of DGs increases. So, many isolating circuit breakers will be needed and the scheme may not be economic. Communication-assisted digital relay approach is presented in  to achieve coordinated operation of OCRs. Complexity and enlarged failure rates are major concerns in this method. Ref.  reviews the protection schemes and coordination techniques in microgrid systems. A neural network and backtracking-based protection coordination scheme for distribution system with DG is presented in .
One approach to control fault current in the presence of DG is the use of Fault Current Limiter (FCL) . FCL basically provides nearly zero impedance in normal operation without energy loss or voltage drop. If a fault occurs, the FCL will insert high impedance within few milliseconds. This reduces the fault currents to lower levels within circuit breakers capabilities . FCLs can be divided into three main categories : passive FCLs, solid-state FCLs, and hybrid FCLs. The passive FCL simply inserts a current-limiting inductance without external control signals. The solid-state FCL is formed by power electronics equipment and sensors. The hybrid FCLs use combination of mechanical switches, solid-state devices, superconducting elements and other technologies to mitigate fault current . FCLs are generally sophisticated and expensive equipment. The FCL size is defined as the impedance value it introduces under fault conditions. FCL cost typically increases when its size increases. Placement and sizing of FCLs in a PDS greatly determine its impact on protection system. In , genetic algorithm-based method was implemented to determine the optimal number and locations of FCLs in a radial distribution system with DG to minimize the total cost of protective devices. In , the optimal FCLs sizes in a distribution system with DG are determined. Nonetheless, the FCLs locations are hypothetically assumed and their cost is not considered. In , FCLs are utilized to restore DOCRs coordination in the presence of DG. So, the optimal OCRs settings without DG are maintained with DG. This avoids any need to OCRs resetting. The latter is a tedious task especially in a large scale PDS. Besides, it may not be adequate to keep OCRs coordination in the presence of DG. However, sizes and locations of FCLs are estimated by trial and error in  and cannot be optimal from performance and cost perspectives.
The study of magneto hydrodynamic gravity-driven convection through an optically thick fluid past an infinite vertical plate is considered very essential in understanding the behavior of the performance of fluid motion in several applications. The problem of gravity-driven convection in a regular fluid past a vertical plate is a classical problem solved by Ostrach . Siegel  was the first to study the transient free-convective flow past a semi-infinite vertical plate by integral method. Convective flows with radiation are also encountered in many industrial processes such as heating and cooling of chambers, energy processes, evaporation from large reservoirs, solar power technology and space vehicle re-entry. Thermal radiation effects of an optically thin gray gas bounded by a stationary vertical plate have been investigated by England and Emery . Soundalgekar and Takhar  have presented the free convective flow of an optically thin radiating gray gas past a semi-infinite vertical plate. Hossain and Takhar  have examined the radiation effects on mixed convection along an isothermal vertical plate.
The combined effects of Hall currents and thermal radiation on the magnetohydrodynamic flows continue to draw the attention of researchers owing to extensive applications of such flows in the context of ionized aerodynamics, nuclear energy systems control, improved designs in aerospace MHD energy systems, manufacture of advanced aerospace materials, etc. There is a vast amount of literature on the magnetohydrodynamic flows taking Hall currents. Pop and Watanabe  have examined the Hall effects on a magnetohydrodynamic free convection past a semi-infinite vertical flat plate. The magnetohydrodynamic free convective heat and mass transfer of a heat generating fluid past an impulsively started infinite vertical porous plate with Hall currents and radiation ack1 inhibitors have been studied by Kinyanjui . Aboeldahab and Elbarbary  have analyzed the Hall effects on a magnetohydrodynamic free convective flow past a semi-infinite vertical plate with mass transfer. Takhar et al.  have studied an unsteady free convective flow past an infinite vertical porous plate taking Hall currents. Aboeldahab and El Aziz  have studied the effects of Hall and ion-slip currents on an MHD free convection from a vertical plate with power-law variation in surface temperature. Chaudhary and Jain  have addressed the Hall effects on an unsteady hydromagnetic flow of a viscous elastic fluid past a vertical porous plate. Abdul Hakeem and Sathiyanathan  have obtained an analytic solution of an oscillatory flow through a porous medium. Effects of Hall currents on an MHD mixed convective flow over a vertical surface in porous medium have been described by Shateyi . Saha et al.  have presented the effects of Hall currents on an MHD natural convective flow past a vertical permeable flat plate with uniform surface heat flux. Ali et al.  have examined the effects of Hall currents on an MHD mixed convection boundary layer flow over a stretched vertical flat plate. Jain and Singh  have described the Hall and thermal radiative effects on an unsteady rotating free convective slip flow. Chaudhary et al.  have presented the effects of Hall currents and thermal radiation on an unsteady free convective slip flow along a vertical plate embedded in a porous medium with constant heat and mass flux. The effects of Hall currents and rotation on an MHD natural convection flow past an impulsively moving vertical plate with ramped plate temperature in the presence of thermal diffusion with heat absorption have been investigated by Seth et al. . Das et al.  have examined the Hall effects on an MHD free convection boundary layer flow past a vertical flat plate. Sarkar et al.  have studied the Hall effects on an unsteady MHD free convective flow past an accelerated moving vertical plate with viscous and Joule dissipations. The effects of Hall currents and radiation on an unsteady MHD flow past a heated moving vertical plate have been discussed by Das et al. . Seth et al.  have investigated the Hall effects on a natural convective flow past a moving vertical plate with heat and mass transfer. Recently, Gireesha  have reported the combined effects of the thermal radiation and Hall currents on boundary layer flow past a non-isothermal stretching surface embedded in porous medium with non-uniform heat source/sink and fluid-particle suspension. The conjugate natural convection flow over a vertical surface with radiation has been presented by Siddiqa . Kataria and Mittal  have developed a mathematical model for velocity and temperature of gravity-driven convective optically thick nanofluid flow past an oscillating vertical plate in the presence of magnetic field and radiation.