Sub-basins with no observed discharge data available for optimiza

Sub-basins with no observed discharge data available for optimization were assigned parameter values of neighbouring sub-basins. The same applied to the downstream sections (e.g. Zambezi at Tete) with no reliable gauge data. The three optimized parameters that vary between (groups of) sub-basins

include: • Soil storage capacity. The first two parameters affect storage of rainfall in the soil for evapotranspiration and thereby control mean volume of flow. Further, they control how long it takes (up to several months) in the rainy season before the soils are sufficiently wet to enable runoff generation (see also Scipal et al., 2005 and Meier et al., 2011). The third parameter defines the fractions of runoff representing surface flow – which leaves the sub-basin within the same month – and base flow with a delayed response

controlling dry season discharge. Observed discharge data of the period 1961–1990 at 14 gauges were JAK inhibitor used to automatically calibrate these three parameters of the water balance model with the Shuffled Complex Evolution search algorithm (Duan et al., 1992). As objective function we used a slightly modified version of the KGE-statistic ( Gupta et al., 2009; modified according to Kling et al., 2012): equation(1) KGE′=1−(r−1)2+(β−1)2+(γ−1)2 β=μsμo γ=CVsCVo=σs/μsσo/μowhere KGE′ is the modified version of the KGE-statistic (dimensionless), r is the correlation coefficient Bleomycin cost between simulated and observed discharge (dimensionless), β is the bias ratio (dimensionless), γ is the variability ratio (dimensionless), μ is the mean discharge in m3/s, CV is the coefficient of variation (dimensionless), σ is the standard deviation of discharge in m3/s, and the indices s and o represent simulated and observed discharge values, respectively. KGE′, r, β and γ have their optimum at unity. For a full discussion of the KGE-statistic and its advantages over the often used Nash–Sutcliffe Efficiency (NSE, Nash and Sutcliffe, 1970) or the related mean squared error see Gupta

et al. (2009). The KGE-statistic offers interesting diagnostic insights into the 4-Aminobutyrate aminotransferase model performance because of the decomposition into correlation (r), bias term (β) and variability term (γ). In this paper we use this decomposition of the model performance to report on the evaluation of discharge simulations at five key locations within the Zambezi basin in the calibration period 1961–1990 as well as in the independent evaluation period 1931–1960. Because of the long observed discharge time-series these statistics were also computed at the gauge Kafue Hook Bridge, even though this gauge was not included in the original set-up of the model. In addition to the parameters of the water balance model, there were also a large number of parameters that had to be specified for the water allocation model. These parameters were not calibrated in a classical sense.

The WISC-R consists of six verbal subtests, namely Information, C

The WISC-R consists of six verbal subtests, namely Information, Comprehension, Arithmetic, Vocabulary Similarities and Digit Span, that are summed to give the Verbal IQ, and of six non-verbal subtests, namely Picture Arrangement, Picture Completion, Object Assembly, Block Design, Coding and Mazes tests, that are summed to give the Performance IQ. The Verbal IQ and Performance IQs are combined to Dapagliflozin clinical trial give a Full-Scale IQ. The WISC-R IQs of the 2011–13 Chinese sample were collected between spring 2011 and summer 2013 when the participants were in sixth grade or had just graduated from sixth grade. Participants were invited to the laboratory, where research assistants, who participated

in an intensive training course, administered the Chinese WISC-R. Ten of the subtests were used, Digit Span and Mazes being omitted. The research assistants were supervised by a Ph.D. trained clinical psychologist who specializes on cognitive brain assessment see more at Nanjing

Brain Hospital. The same training procedure as described in detail in Liu and Lynn (2013) was followed. The IQ test was administered over the course of one hour in a quiet room in Jintan Hospital. Each test was scored by two individuals to minimize scorer bias. This procedure for data collection was approved by the research ethics committee of Jintan Hospital and the University of Pennsylvania. Written consent was obtained from parents and written assent from children was collected prior to initiation of the study. Table 1 gives the mean scaled scores and standard deviations for boys and girls on the subtests, and the verbal, performance and full scale IQs on the Chinese WISC-R of the 2011–2013 Jintan

sample. Also given are the differences between the means of the boys and girls expressed as ds (the difference between the means divided by the pooled standard deviation, with minus signs showing that girls obtained higher means than boys), the t values using independent sample t-tests for the statistical significance of the differences between the means of the boys and girls, and the variance ratios (VR) as a measure of the sex differences in variability calculated as the standard deviation of the males divided by the Mannose-binding protein-associated serine protease standard deviation of the females. Thus, a VR greater than 1.0 indicates that males had greater variance than females. Table 2 gives sex differences on the WISC-R in China and in the standardization sample (N = 2200) in the USA given by Jensen and Reynolds (1983). The results provide six points of interest. First, it is shown in Table 1 that in the present Chinese sample boys obtained a significantly higher Full Scale IQ than girls by 0.25d, the equivalent of 3.75 IQ points. This figure is higher than the average boys’ advantage of 2.25 IQ points on the Wechsler Full Scale IQ in eight standardization samples of the Wechsler tests for children noted in the introduction.

All previous studies that reported a costimulatory role of this m

All previous studies that reported a costimulatory role of this molecule were based on the use of monoclonal antibodies to trigger the CD150 molecule on T cells (Cocks et al., 1995, Aversa et al., 1997 and Howie et al., 2002). CD150 is a self-ligating molecule and no other binding partners have been described. Thus, we wanted to analyze whether the costimulatory effect was also observed upon engagement of T cell-expressed CD150 with its natural ligand. Therefore, we generated stimulator cells expressing CD150 in conjunction with anti-CD3. When co-culturing these stimulator cells with human T cells, no significant contribution of this interaction

to T cell proliferation Bleomycin and cytokine production was observed (Fig. 5B,C). In some of our experiments reduced proliferation rates of human T cells were observed in the presence of human CD150 but additional experiments are required to

confirm that CD150 can function as a negative regulator of T cell responses. During APC–T cell interaction Everolimus in vivo a complex interplay of numerous cell surface molecules modulates cellular immune responses by either enhancing or inhibiting T cell receptor complex signalling. Thus, assessing the function of individual costimulatory ligands using natural APC is a difficult task. With our T cell stimulator cells we have generated an experimental tool for studying individual costimulatory ligands in a cellular system, but detached from the context of numerous other molecules involved in the regulation of T cell activation that are expressed on professional APC. Whereas similar cellular systems that have been termed artificial APC (aAPC)

use cells engineered to express Fc-γ receptors (CD32 or CD64) and depend on the addition of anti-CD3 antibodies (Thomas et al., 2002, Suhoski et al., 2007 and Gong et al., 2008) we used cell lines that stably express membrane-bound anti-CD3 antibody fragments. Using different anti-CD3 expression constructs we have generated PI-1840 two cell clones that stably express different levels of anti-CD3 antibody fragments: A construct where the anti-CD3 antibody fragments are linked to the transmembrane domain of human CD28 molecules yielded Bw-aCD3low stimulator cells that give a weak signal 1 to human T cells, whereas a construct encoding anti-CD3 antibody fragments fused to the human CD14 molecule was used to generate cells expressing high levels of GPI-anchored anti-CD3 antibody fragments (Bw-aCD3high; Fig. 1). The GPI-anchored anti-CD3 antibody fragment is efficiently targeted to lipid rafts and has also successfully been used for the stimulation and manipulation of human T cells with immunosomes — virus-like particles decorated with TCR/CD3 ligands, costimulatory molecules and modified cytokines (Derdak et al., 2006, Kueng et al., 2007, Leb et al., 2009 and Kueng et al., 2010).

One explanation may relate to metabolic differences between speci

One explanation may relate to metabolic differences between species. Methamidophos can cause a cholinergic crisis in hens so strong that it will be lethal before the onset of clinical signs of OPIDN. Therefore, in hens, the enantiomer with a higher affinity for AChE may be less metabolized than in other species, and the enantiomer that exhibits greater affinity for NTE may be less

metabolized in humans. ALK inhibitor Studies done only with tissue from hens could lead to the erroneous conclusion that methamidophos does not induce OPIDN in humans. Therefore, the combination of in vitro studies on human and hen enzymes and studies of metabolism in hens could predict whether the OP is capable of generating OPIDN in both species ( Battershill et al., 2004). There are several research studies that describe calpain activation in hens after intoxication by a neuropathic OP (El-Fawall et al., 1990, Choudhary and Gill, 2001 and Emerick et al., 2010). In Wallerian-type degeneration an excessive intake of calcium

by the cell can activate calpain. This enzyme promotes digestion of the terminal portion of axons, preventing the transmission of nerve impulses to the post-synaptic cells (Moser et al., 2007). In the present work, an in vitro calpain assay demonstrates that only mipafox was able to promote calpain activation. check details This effect was greater with human neuroblastoma cells, probably because they are relatively pure compared to the multiple cell types found in a brain homogenate. An early study by Ehrich et al. (1997) showed that capability to cause or not cause OPIDN could be predicted by ratios of the IC50 values in human and mouse RVX-208 neuroblastoma cells. Later, Sogorb et al.

(2010) proposed an alternative methodology to predict whether an OP is able to induce OPIDN. This method is based on the comparison of the in vitro inhibition (and aging of NTE) of both enzymes (NTE and AChE) in human and hen cells. The authors tested 10 OPs (6 neuropathic and 4 non-neuropathic), and stated that if the IC50NTE/IC50AChE ratio is greater than five, then the compounds would not be able to induce the neuropathy. This was because the concentrations necessary for inhibition and aging of greater than 70% of NTE would not be compatible with the survival of individuals due to strong cholinergic crisis before the onset of delayed effects. However, if the IC50NTE/IC50AChE ratio is less than five, the OP may be a neuropathic compound if it has the ability to induce the “aging” reaction. Applying this hypothesis to the results of this in vitro study, we conclude that the (−)-methamidophos form would not be able to generate OPIDN in humans and hens, even if the aging reaction of NTE was to occur. However, other variables exist in vivo, such as differences in metabolism.

M C B holds European and U S patents on this technology “

M.C.B. holds European and U.S. patents on this technology. “
“Bone marrow-derived cells have been shown to have beneficial properties for treatment of brain ischemia (Maltman et al., 2011, Mendez-Otero et al., 2007 and Mezey, 2007). Although they have been described as multipotent cells, with supposed capability to regenerated some lost tissue cells (Crain et al., 2005, Krause et al., 2001 and Shyu et al., 2006), their main mechanisms of action has been GSK126 shown to be chemoattraction to lesioned tissues and release of several cytokines and trophic

factors (Maltman et al., 2011, Shyu et al., 2006 and Takahashi et al., 2006). The use of bone marrow-derived mesenchymal stem cells (MSCs) has been extensively shown as a promising therapeutic approach (Maltman et al., 2011). However, therapeutic use of MSC involves cell cultivation for several weeks, which hinders autologous transplantation in the acute phase of brain ischemia, when treatment should be more successful. Alternatively, some studies have used bone marrow mononuclear cells (BMMCs), a cell fraction that contains MSCs, hematopoietic stem cells, hematopoietic progenitor cells and endothelial progenitor

cells (Orkin, 2000, Wang et al., 2008 and Weissman et al., 2001). BMMCs can be harvested in 1.5–6 h and autologously administrated without any previous cultivation (Battistella et al., 2011, Brenneman et al., 2010, APO866 cell line Iihoshi et al., 2004 and Savitz et al., 2011), which allows treatment during the acute phase (Mendez-Otero et al., 2007). Indeed, BMMCs has been shown to be as beneficial as MSCs to treat acute brain ischemia in animal models (de Vasconcelos dos Santos et al., 2010, Giraldi-Guimarães et al., 2009, Iihoshi et al., 2004, Kamiya et al., 2008 and Yang et al., 2011). Several previous reports have demonstrated induction of functional recovery by MSCs and BMMCs in sensorimotor

tests using different models of brain ischemia (Chopp and Li, 2002, de Vasconcelos dos Santos et al., 2010, Giraldi-Guimarães et al., 2009, Iihoshi et al., 2004, Kamiya et al., 2008 and Yang et al., 2011). However, functional tests usually Sodium butyrate applied to evaluate treatment-induced improvements of sensorimotor function after brain ischemia involves unsophisticated motor patterns of limbs, which do not require skill and previous training to be performed (e.g., spontaneous postural support, flexion, placing during locomotion, balance and tactile response) (Schaar et al., 2010 and Schallert, 2006). Although recovery of these motor patterns should represent significant functional outcome, functional analyses should be extended to evaluate whether cell therapies are also able to promote recovery of skilled movements. Unlike previously thought, rat skilled forepaw movements has been shown to be similar to primate hand movements, having single digit movements controlled by motor cortex (Alaverdashvili and Whishaw, 2008).

In addition to its importance as hydropower resource, the Raquett

In addition to its importance as hydropower resource, the Raquette River serves as a water source for several communities along its banks, as a recreational resource, and as an important cultural resource for the Native American community at Akwesasne. Along the course of its length the river traverses three very distinct geological terranes including the Adirondack

Highlands, Adirondack Lowlands, and St. selleck chemicals Lawrence River Valley (Chiarenzelli et al., 2012). The approximate center of the Adirondack topographic dome, the High Peaks Region, is east of the Raquette River drainage basin and underlain by the large Marcy Anorthosite massif. The anorthosite is surrounded by a complex assemblage of highly metamorphosed Precambrian crystalline bedrock lithologies ranging in age from about XL184 chemical structure 1.00 to 1.35 billion years old that make up what is referred to as the Adirondack Highlands (Regan et al., 2011). In addition to its domal topographic expression, this area is characterized by highly deformed and metamorphosed igneous rocks, many of which were intruded along with the anorthosite

deep into the roots of an ancient mountain belt. This mountain belt was part of a global system of continental collisions (i.e. orogenic events) that resulted in the formation of the supercontinent of Rodinia by 1.0 billion years ago. The Adirondacks are part of a continental-scale belt of

highly eroded crystalline rocks of similar age and origin, known as the Grenville Province, which can be traced in North America from Greenland to Mexico and beyond. With minor exceptions, the rocks in the Adirondack Highlands generally have moderate to limited capacity to buffer acidity (Colquhoun et al., 1981). The Adirondack Lowlands are located northwest of the Adirondack Highlands and are separated from them by a ductile fault known as the Carthage-Colton Shear Zone. In the Lowlands rocks have been dropped down into their Amisulpride present position after the cessation of mountain building at about 1.0 billion years ago. While still highly deformed and metamorphosed, they record slightly lower metamorphic conditions indicating a position higher in the crust during mountain building than the Highlands. The Lowlands are composed predominantly of less resistant metamorphosed sedimentary rocks developed from a sequence of limestones, sandstones, shale, and evaporitic rocks (Chiarenzelli et al., 2011). They have been intruded by several suites of meta-igneous rocks which comprise a relative small percentage of the current surface area of the Lowlands. The metasedimentary rocks exposed in the Lowlands are also present in the Highlands.

In the case of stenosis: >5 endoscopic dilatations, stent placeme

In the case of stenosis: >5 endoscopic dilatations, stent placement, or incision therapy); or fatal (death attributable to procedure <30 days or longer with continuous hospitalization).22 Statistical analysis was performed with mTOR inhibitor a statistical software package (Statistical Package for the Social Sciences 14.0.2; SPSS Inc, Chicago, Ill). Data with a normal distribution were described with the mean and standard deviation, whereas data with a skewed distribution

were described by the median and interquartile ranges (IQR) or ranges. Confidence intervals (CI) of the proportions were calculated with Confidence Interval Analysis, version 1.0.23 Between January 2006 and October 2008, 26 consecutive patients (21 men, mean [± SD] age 66 ± 10.6 years) were included in

this study. Patient characteristics are described in Table 2. Median BE length was C9M11 cm (IQR C8-10, M10-12). None of the patients showed signs of active reflux disease, yet 13 patients (50%) were found to have reflux stenosis at the proximal Akt inhibitor end of the BE segment. These stenoses were generally asymptomatic and allowed passage of the therapeutic endoscopes. In 3 patients, however, endoscopic bougienage of the reflux stenosis was required before treatment to facilitate the introduction of an ER cap and RFA catheters. Eighteen patients underwent ER of visible abnormalities before RFA. The ER cap technique was used in 5 patients and multi-band mucosectomy in 13 patients. The ER specimens showed early cancer in 11 patients (intramucosal [n = 10], sm1 [n = 1], all with good or moderate differentiation and no lymphatic/vascular invasive growth), HGIN in 6 patients, and LGIN in 1 patient. Before RFA, and after ER if applicable, all patients had flat mucosa without visible abnormalities, Selleck Rucaparib with random mapping

biopsies showing HGIN in 16 and LGIN in 10 patients. In 2 patients (8%), the treatment protocol was discontinued because of unrelated comorbidity (psychiatric disorder and lung cancer). In both, at the last endoscopy before discontinuation, endoscopic regression of BE was 99% without histological information available. These patients were excluded from analysis of the primary endpoints. CR-neoplasia was achieved in 20 of 24 patients: 83% (95% CI, 63%-95%). CR-IM was achieved in 19 of 24 patients: 79% (95% CI, 58%-93%) (Figure 2 and Figure 3). In 4 patients (15% [95% CI, 4%-35%]), the RFA treatment was discontinued after 1 to 3 sessions because of poor healing and no or almost no regeneration of neosquamous mucosa (Fig. 4). These patients were therefore considered as failures for the primary endpoints of the study (CR-neoplasia and CR-IM). Patients achieved CR-neoplasia and CR-IM after a median of one (IQR 1-2) circumferential and two (IQR 1-3) focal ablations. Three patients underwent an escape ER for persisting BE islands after the maximum number of RFA treatments.

1A and B) High expression of Ki67 was observed following polyclo

1A and B). High expression of Ki67 was observed following polyclonal T cell stimulation

with αCD3/αCD28; Ki67 was observed responses were high on day 1 already, peaked on day 3, and declined thereafter (Fig. 1A and C). Next, we assessed proliferation by Ki67 detection in whole blood from 15 healthy donors, after 6-day culture with no antigen, or with PPD. All donors had undetectable or very low frequencies of Ki67+ CD4+ T cells in unstimulated blood (median, 0.07%). PPD stimulation resulted in higher frequencies of Ki67+ CD4+ T cells in all donors (median, Afatinib molecular weight 46.1%, Fig. 1D). We also determined whether proliferation could be detected by assessing Ki67 expression in PBMC. Again, Ki67 expression identified in vitro CD4+ T cell proliferation; frequencies of Ki67+ cells after PPD stimulation consistently

exceeded those in unstimulated PBMC, at a median of 21.7% ( Fig. 1E). These data suggest that in 6-day PBMC or whole blood culture with antigen, Ki67 expression is up-regulated in T cells undergoing in vitro proliferation. Next, we compared our Ki67-based proliferation assay with more traditional flow cytometric proliferation assays, i.e., those measuring BrdU incorporation and dye dilution of OG (Fig. 2). BrdU is incorporated into cells undergoing DNA synthesis, and is typically added during the last 2 to 24 h of a proliferation assay; in this study we added BrdU for the last 5 h of the 6-day culture. The frequency of Ki67+ CD4+ T cells was higher than the frequency of BrdU+ cells after whole blood stimulation with PPD or TB10.4 protein (Fig. 2A, B and C). Importantly, all BrdU+ cells co-expressed http://www.selleckchem.com/products/erastin.html Ki67 (Fig. 2A). The OG

assay requires uniform labelling of cells prior to long-term culture. In contrast to results from the BrdU assay, the OG and Ki67 assays yielded remarkably similar frequencies of proliferating, specific T cells; Ki67+ and OGlow CD4+ T cell frequencies were not different in PPD or TB10.4-stimulated PBMC (Fig. 2D, E and F). Frequencies Amobarbital of Ki67+ CD4+ T cells correlated strongly with BrdU+ CD4+ T cell frequencies (Fig. 3A and B). Similarly, a strong correlation was found between frequencies of antigen-specific Ki67+ and OGlow CD4+ T cells (Fig. 3C and D). These data show that frequencies of proliferating T cells detected by Ki67 expression agree with frequencies detected with conventional proliferation assays. The functional capacity of cells that have expanded during the 6-day culture may be assessed by short-term polyclonal re-stimulation with PMA and ionomycin on day 6. This induces cytokine production, which can be measured by intracellular staining. We compared expression of IFN-γ, IL-2 and TNF-α by Ki67+ CD4+ T cells with expression of these cytokines in BrdU+ or OGlow CD4+ T cells. When Ki67 and BrdU assay results were compared, similar expression of IFN-γ and TNF-α was observed in proliferating CD4+ T cells.

Many laboratories have used commercially-available

cigare

Many laboratories have used commercially-available

cigarettes for the generation of smoke extracts. Such an approach however may lead to inter-laboratory differences since the smoke chemistry of different cigarette brands is diverse and this can give rise to diversity in cellular responses. For this reason, we suggest that the use of standardised reference cigarettes, such as the 3R4F reference cigarette (University of Kentucky College of Agriculture; http://www.ca.uky.edu/refcig/3R4F%20Preliminary%20Analysis.pdf), IDH inhibitor cancer would provide better uniformity of experimental responses both within the same laboratory and also between laboratories. With respect to experimental controls, the biological effects of smoke derived from a PREP should be compared to that of a conventional, commercially-available product (Institute of Medicine, 2012). A further issue concerning the exposure of in vitro models to cigarette smoke is the metabolic activation Talazoparib clinical trial of the smoke extracts and their constituents. Certain cigarette smoke toxicants, for example benzo(a)pyrene, require metabolic activation in order to exert their effects ( Ma and Lu, 2007). Importantly, many in vitro cell cultures lack metabolic capacity and this can

be circumvented by either metabolically-activating the cigarette smoke extracts using other systems with this capacity (e.g. liver hepatocytes or liver extracts) before exposure, by activating the extract using a mammalian liver microsomal fraction such as S9, or by choosing primary cultured Carnitine palmitoyltransferase II cells with demonstrated active metabolic pathways. An approach that avoids the issue of metabolic activation of cigarette smoke extracts for in vitro models involves exposing cells to human sera obtained from smokers and non-smokers

( Fig. 2C). This approach has proven particularly useful, for example, in gaining mechanistic insight into the role of NO biosynthesis in the pathogenesis of endothelial dysfunction in cardiovascular disease ( Barua et al., 2001 and Barua et al., 2003). Importantly, by performing clinical measurements of arterial reactivity by measuring flow-mediated endothelium-dependent vasodilatation in the subjects from whom the sera were obtained, it was possible to demonstrate a positive correlation between the clinical and the in vitro effects of cigarette smoking ( Barua et al., 2001) and this may add support to the appropriateness of this approach. More recently, Barbieri et al., (2011) demonstrated that sera from smokers elicited a stronger oxidative stress response in endothelial cells than sera from non-smokers, in terms of ROS production, p47phox translocation to the plasma membrane, and cyclooxygenase 2 (COX-2) mRNA and protein expression.

The entire time series or the part of it that corresponds to tren

The entire time series or the part of it that corresponds to trends or oscillatory modes

can be reconstructed by using linear combinations of principal components and E7080 solubility dmso eigenvectors, as: equation(3) Xi=X(iΔt)=1M∑k=1M∑i+j=s[(PC)k(i)][(E)k(j)]where k is the set of T-EOFs on which reconstruction is based. The basic idea in SSA is simple: a PCA is done with the variables analyzed being lagged versions of a single time series variable. We construct an input matrix that contains the “lagged” time series X*(iΔt) where i = 1, …., N are the lags and Δ is the time increment (the “size” of the lag). The lagged covariance matrix Cij (Eq. (2)) contains covariances between the time series at all possible combinations of lags. The T-PCs obtained by the decomposition of Cij can be interpreted as moving averages of the original time series, the averages being weighted by the coordinates of the T-EOFs. The decomposition in PCs given in Eq. (3) allows us to identify the different hidden processes in the signal X*(iΔt). The first T-PCs will be naturally associated with deterministic mechanisms that account for most of the variance of the series. The remaining T-PCs correspond to information that cannot be separated from the background noise. In this paper, the spatiotemporal behavior of periods of excess and water deficit

was determined through a PCA applied to the fields of SPI at different time scales.

The vulnerability Nintedanib of the region to EPE was determined by defining the spatial extent of these periods by means of the percentage of grid points in wet or dry conditions for each month of the time series. SSA was applied to the time series of interest looking for significant signals in the LFB (trends or oscillatory modes). PCA was applied to the field of SPIn (t) (n = 6, 12 and 18 month) to define the spatial distribution of aij correlations for SPI time series at each grid point with the principal components Pazopanib in vivo PCj (j = 1, 2, 3). The temporal behavior of the PCjn (t), j = 1, 2, 3; n = 6, 12 and 18 months series was determined by applying SSA, looking for low frequency signals in the LFB and using a window length M of 360 months (30 years). The first PC explained a high percentage of the total variance for all SPIn (t) time series analyzed (49.5%, 52.7% and 54.7% for n   = 6, 12 and 18 month, respectively). Correlation of PC1n (t) with SPI time series at each grid point, expressed by a  i1, resulted in positive values in all cases, proving to be the component that is closest related with variables (SPI time series). We determined the correlation of the PC1n with each SPI spatial average time series in the region ( SPIn (t)¯, n = 6, 12 and 18 months). The obtained coefficients in all cases were close to 0.999, indicating that the average areal behavior of SPI fields could be explained by PC1n (t) series.