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With the global spread of English as the lingua franca for academic publishing, non-native researchers and university students are constantly facing linguistic barriers including insufficient vocabulary knowledge in writing for publication. This persistent need motivated the development of a good number of corpus-based word lists for frequently used academic and technical words in research articles across disciplines. Nevertheless, despite its importance in corpus-based study of language for word list development, replication research has received far less attention in this line of inquiry. The current study aimed to address this gap and replicated two published studies that investigated the use of academic vocabulary in applied linguistics research articles. To this end, research articles published from 2010 to 2020 in 20 well-known journals in the field were collected, and a corpus with around 48 million words was compiled and analyzed. The findings indicated that academic vocabulary accounted for 11.46% of the corpus, which is similar and close to the reported coverage of the AWL in replicated studies. However, regarding the frequently occurring academic and non-academic content words, the findings showed considerable variation with respect to the results reported earlier. In light of these findings, the study highlighted the importance of replication research to test the reliability of corpus-based vocabulary studies that developed field-specific academic word lists. Finally, the study developed an updated version for applied linguistics academic word list, that might be regarded as a resource and guide for the vocabulary learning component of the relevant EAP programs in the field.

In this experimental work, the effects of multiwall carbon nanotubes (MWCNTs) on electrical characteristics of zinc oxide–MWCNT–high-density polyethylene composite varistors have been investigated. All the samples were made at the temperature of 130 °C and pressure of 60 MPa by the hot-press method. Results show that increasing zinc oxide content in the mixture increases breakdown voltage up to 170 V, where the highest nonlinear coefficient (α ~ 13) corresponds to the samples with 95 wt% of ZnO. Results with regard to the effects of MWCNT as an additive reveal that increasing its content from 1 to 2.5% in the composites, the breakdown voltage decreases to 50 V, but the highest nonlinear coefficient (~ 14) corresponds to the sample with 1.5% of MWCNT content. It is also revealed that, heat treatment of the sample at a constant temperature of 135 °C and different time intervals from 2 to 10 h, the sample with 6 h annealing time shows maximum breakdown voltages (Vb = 140 V) with the highest nonlinear coefficient (~ 14). Investigation of the potential barrier height of samples shows a complete consistency with the breakdown voltage variations. The results have been justified regarding XRD patterns and SEM micrographs of samples.

Balance impairment is a common problem in all age groups. There are several tools to assess balance. Functional reach test (FRT), single-leg stance (SLS) test, timed up and go (TUG) test, and TUG with the cognitive dual-task (TUGcog) are commonly employed balance tests. The current study aimed to determine the normative values of FRT, SLST, TUG, and TUGcog across age groups and genders in healthy Iranian adults.We designed a cross-sectional study, and 240 healthy adults (120 males and 120 females) in six age groups (18-29, 30-39, 40-49, 50-59, 60-69, ≥70 years) completed FRT, SLST, TUG, and TUGcog based on the Persian version of BESTest instructions.There were significant age-specific declines in balance performances. Gender had effects on 18-29 years and older adults (≥60 years), and males performed better than females. Male and females had similar performance on the TUG and TUGcog tests in 60-69 years (p 0.05).The normative values of FRT, SLS, TUG, and TUGcog provided for healthy Iranian adults increase the clinical utility of tests, and serve as a reference to estimating the individuals' balance performance across age and gender groups.

Low back pain (LBP) is a common health condition in populations. Limited large-scale population-based studies evaluated the prevalence and predictors of LBP in developing countries. This study aimed to evaluate the prevalence and factors associated with LBP among the Iranian population.We used baseline information from the Prospective Epidemiological Research Studies in Iran (PERSIAN), including individuals from 16 provinces of Iran. LBP was defined as the history of back pain interfering with daily activities for more than one week during an individual's lifetime. Various factors hypothesized to affect LBP, such as age, sex, marital status, educational status, ethnicity, living area, employment status, history of smoking, body mass index (BMI), physical activity, sleep duration, wealth score, history of joint pain, and history of morning stiffness in the joints were evaluated.In total, 163770 Iranians with a mean age of 49.37 (SD = 9.15) were included in this study, 44.8% of whom were male. The prevalence of LBP was 25.2% among participants. After adjusting for confounders, the female gender [OR:1.244(1.02-1.50)], middle and older ages [OR:1.23(1.10-1.33) and OR:1.13(1.07-1.42), respectively], being overweight or obese [OR:1.13(1.07-1.19) and OR:1.21(1.16-1.27), respectively], former and current smokers (OR:1.25(1.16-1.36) and OR:1.28(1.17-1.39), respectively], low physical activity [OR:1.07(1.01-1.14)], and short sleep duration [OR: 1.09(1.02-1.17)] were significantly associated with LBP.In this large-scale study, we found the lifetime prevalence of LBP to be lower among the Iranian population in comparison to the global prevalence of LBP; further studies are warranted to evaluate the causality of risk factors on LBP.

Emerging evidence suggests that biofluid-based biomarkers have diagnostic and prognostic potential in traumatic brain injuries (TBI). However, owing to the lack of a conceptual framework or comprehensive review, it is difficult to visualize the breadth of materials that might be available. We conducted a systematic scoping review to map and categorize the evidence regarding biofluid-based biochemical markers of TBI. A comprehensive search was undertaken in January 2019. Of 25,354 records identified through the literature search, 1036 original human studies were included. Five hundred forty biofluid biomarkers were extracted from included studies and classified into 19 distinct categories. Three categories of biomarkers including cytokines, coagulation tests, and nerve tissue proteins were investigated more than others and assessed in almost half of the studies (560, 515, and 502 from 1036 studies, respectively). S100 beta as the most common biomarker for TBI was tested in 21.2% of studies (220 articles). Cortisol was the only biomarker measured in blood, cerebrospinal fluid, urine, and saliva. The most common sampling time was at admission and within 24 h of injury. The included studies focused mainly on biomarkers from blood and central nervous system sources, the adult population, and severe and blunt injuries. The most common outcome measures used in studies were changes in biomarker concentration level, Glasgow coma scale, Glasgow outcome scale, brain computed tomography scan, and mortality rate. Biofluid biomarkers could be clinically helpful in the diagnosis and prognosis of TBI. However, there was no single definitive biomarker with accurate characteristics. The present categorization would be a road map to investigate the biomarkers of the brain injury cascade separately and detect the most representative biomarker of each category. Also, this comprehensive categorization could provide a guiding framework to design combined panels of multiple biomarkers.

The purpose of this work was to investigate the effect of hydroalcoholic extracts from the peel (APE) and pulp (APP) of a traditional apple variety of central Italy, the ‘Mela Rosa dei Monti Sibillini’, on the damage caused by renal ischemia/reperfusion injury (IRI) in rats. Thirty mg per kg b.w. of the extracts were administered intraperitoneally to male adult Wistar rats 3 days before the induction of IRI by pedicle clamping. A significant decrease in the levels of malondialdehyde (MDA), tumor necrosis factor-α (TNFα), interleukin 1 beta (IL-1β) and nuclear factor-κB (NF-κB) was observed in the groups pre-treated with APE when compared with IRI rats. The chemical composition of APE was determined by HPLC-DAD-MSn highlighting a significant amount of proanthocyanidins (52.9 mg g−1), flavonols (42.27 mg g−1) and dihydrochalcones (11.75 mg g−1). These findings indicated that this ancient apple variety is a promising source of nutraceuticals and functional foods helpful to manage complications of renal disorders.

The nonlinear properties and frequency characteristics of ZnO–polypyrrole composites were investigated at 200 Hz–5 MHz frequency interval with different zinc oxide contents. Samples were prepared using hot press method at 130 °C. Results show an optimum point for breakdown voltage at ZnO content of 70%. Breakdown voltage decreases from 590 to 380 V and after that tends to increase from 450 to 740 V due to the absence of polypyrrole at grain boundaries. No matter how breakdown voltage behaves, nonlinear coefficient increases from 4.2 to 9 by increasing ZnO content because of the increase in acceptor-like states at grain boundaries by increasing ZnO content. The electrical parameters such as dielectric constant, dielectric loss and series resistance of samples show a strong dependence on frequency especially below 1 kHz. These parameters fall off by increasing frequency up to 1 kHz, which is related to charge transportation through the Schottky barrier at grain boundaries. The high dielectric constant of samples below 1kHz is related to the Maxwell–Wagner polarization at grain boundaries. The presence of different anomalies at different frequency intervals is related to interfacial polarization because of different structures of grains and intergranular layer with a huge difference in conductivity.

The effect of changes in sintering temperature on electrical properties and microstructure of ZnO–polyaniline– polyethylene composite ceramics, prepared in disk form at the pressure of 60 MPa and at five different temperatures, has been investigated. Increasing sintering temperature from 30 to 120 °C noticeably reduces breakdown voltage from 830 to 610 V. Further increase in sintering temperature causes breakdown voltage to increase. Interface voltage barrier height behaves differently when sintering temperature increases, which is in contrast to breakdown voltage behavior. These samples have a very low leakage current, a factor which indicates low degradation. Then again, the higher the sintering temperature gets, the less the nonlinear coefficient becomes. In addition, each sample has hysteresis which decreases through increase of sintering temperature up to 120 °C. Further increase in sintering temperature, however, causes the hysteresis loop to spread. Regarding UV spectra of the samples, it is revealed that there are three impurity levels whose behaviors against sintering temperature are subtractive. Analysis of composite samples by scanning electron microscopy indicates that their microstructure consists of grains and grain boundaries. Resistivity of grain boundaries is the main responsible factor for these changes in varistor characteristic as a function of sintering temperature.

Introduction: Prominent prognostic parameters that reflect the severity of coronavirus disease 2019 (COVID-19) to adopt an appropriate therapeutic approach are not fully identified. This systematic review and meta-analysis aimed to explore the association between lymphocyte variation and disease severity in COVID-19 individuals. Methods: We searched Web of Science, Scopus, PubMed, EMBASE and WHO website to retrieve studies investigating lymphocyte subset counts in non-severe and severe cases of COVID-19. The pooled standardized mean difference (SMD) between two groups and the pooled average count of each lymphocyte subset were assessed by employing a random-effect model. Results: Thirty-nine investigations on 5087 participants, including 3578 non-severe patients and 1509 severe patients, were included. The pooled analysis showed that non-severe patients had higher total T lymphocytes (SMD = 1.01; 95% CI: 0.82, 1.20; I2 = 75.7%), T helper cells (SMD = 1.07; 95% CI: 0.85, 1.28; I2 = 85.4%), T cytotoxic cells (SMD = 1.07; 95% CI: 0.82, 1.32; I2 = 87.1%), B cells (SMD = 0.72; 95% CI: 0.45, 0.98; I2 = 79.7%), and natural killer cells (SMD = 0.65; 95% CI: 0.47, 0.84; I2 = 63.1%) than severe patients and the average count of the corresponding lymphocyte signatures in non-severe patients/severe patients were 878.88/448.40, 493.12/268.96, 311.91/158.91, 177.09/110.37, and 155.02/103.09 cells/μL, respectively. Conclusion: Lymphopenia may be a dilemma in COVID-19 management because over-activation of lymphocytes may lead to cytokine storm or acute respiratory distress syndrome (ARDS). In contrast, lymphopenia may increase SARS-CoV-2 amplification and COVID-19 severity. Therefore, novel therapies targeting lymphocyte proliferation or contraction may counterbalance lymphocyte counts in these patients.

We investigated the effect of water and its amount on conductivity of exfoliated graphite nano-platelets (XGnP) under mechanochemical methods. Results showed that, by increasing water content in the system, conductivity of the product increased from 109 to 219 S/cm and the nonlinear coefficient decreased from 14.5 to 10.5. Electrophysical studies of the samples prepared from zinc oxide-XGnP-high density polyethylene showed strong dependency of nonlinearity and breakdown voltage to the XGnP and zinc oxide content in the mixture. Accordingly, by increasing the XGnP content from 1 to 4% at a constant zinc oxide content (80%), the nonlinear coefficient decreased from 10.5 to 4.1.

Correction for ‘Protective effects of hydroalcoholic extracts from an ancient apple variety ‘Mela Rosa dei Monti Sibillini’ against renal ischemia/reperfusion injury in rats’ by Hasan Yousefi-Manesh et al., Food Funct., 2019, 10, 7544–7552.

Herein, we report the efficiency of mechanochemical method as a simple, green and environmental approach to synthesis of exfoliated graphite (EG) consisting of multi and few layers of graphene. The layers of graphite expand under mild conditions using citric acid as a cheap and non-toxic intercalation and along with potassium permanganate as oxidation lead to exfoliation of graphite at room temperature. Measured conductivity of EG was 120 S/cm. Although EG has high conductivity, mixing it with zinc oxide (ZnO) and polyethylene shows great nonlinear properties. Results indicate that these combinations could be used as a varistor to protect electronic circuits. In addition, experimental results suggest that by increasing EG content in the mixture, breakdown voltage and nonlinear coefficient are both decreased from 360 to 40 V and 11.25 to 5.22 respectively. Finally, it was found that heat treatment on ZnO led nonlinear coefficient to decrease, the sample sintered at a lower temperature showing the highest nonlinearity.

This literature review aims to highlight the possible causes, complications, and management of this event from previously published studies discussing dehydration in critically-ill patients admitted to the emergency room (ER). In general, the administration of fluids has been used in the ER for critically-ill patients for many purposes. These include the optimization and adjustment of body fluids and electrolytes, increase renal protection against contrast, enhance uric acid, globins, caloric intake, and as an adjuvant to ameliorate the potentiality of certain medications or to dilute them. Many etiologies have been accused to cause dehydration in critically-ill patients. These include the fasting strategy that patients are obliged to whenever undergoing a surgical operation. Kidney, heart, and liver injuries have also been associated with patients’ dehydration. Old age and the presence of other co-morbidities diabetes insipidus and uncontrolled diabetes can also aggravate the condition. Mental affection is the main complication that patients with severe dehydration might complain about. Other complications might include aggravation of heart failure, and skin diseases, and deterioration of the kidney functions and other cellular processes that require adequate nourishment for their daily normal functions. Mortality is also a serious common complication, especially within elderly patients. Although the management of dehydration can be easily achieved by fluid administration, fluid overload can aggravate the underlying complications and develop others. Therefore, the main challenge here would be to frequently monitor patients during fluid administration and resuscitation to prevent this side effect.

Aim Depression and anxiety are the most common psychological disorders among obese patients. Therefore, understanding the risk factors for this relationship is essential. This study was carried out aiming to assess the association of anxiety and depression with BMI and to evaluate the related risk factors. Methods This cross-sectional study was conducted on a large sample of 732 overweight and obese patients. Hospital Anxiety and Depression Scale (HADS) questionnaire was used for measuring depression and anxiety. Additionally, for all subjects, body mass index (BMI), percentage of body fat (PBF) and total soft lean mass (SLM) were measured using AVIS 33 body composition analyzer. Results We found that BMI and PBF were significantly higher among overweight/obese patients who had anxiety or depression. Depression and anxiety were more frequent among housekeepers. Anxiety (p Conclusions Obesity/overweight associated with the development of anxiety and depressive symptoms irrespective of sleep behavior. On the other hand, depression and anxiety were found to be the potential risk factors for developing obesity. These results indicate a direct association between psychosocial state and obesity.

Background: Osteoarthritis (OA) is a highly prevalent chronic degenerative joint disease with different risk factors, which need to be investigated in order to perform more appropriate interventions in earlier phases of Osteoarthritis. Objectives: Therefore, the aim of this study was to determine the correlation between hip morphology and hip Osteoarthritis. Methods: This cross-sectional study was conducted on patients aged 15 to 60 years old with hip problems, diagnosed with hip Osteoarthritis, compared with healthy individuals as the control group. Then radiographic parameters, such as alpha angle, acetabular angle of sharp (AA), lateral center-edge angle (LCEA), femoral neck-shaft angle (FNA), coxa profunda, acetabular protrusio, crossover sign, posterior wall sign, and the ischial sign were measured by pelvic (AP) X-ray, using PACS systems in both groups. Results: This study found that alpha angle and AA were significantly greater in OA patients as compared to healthy individuals (P 0.05). By grouping studied angles, it was found that the frequency of alpha angle > 55°, AA > 38°, and LCEA > 40° were significantly higher in the OA group as compared to the control group (P < 0.05). Furthermore, the researchers observed that the frequency of acetabular protrusio (P = 0.013) and posterior wall sign were significantly higher in the OA group as compared to healthy individuals (P < 0.05). Conclusions: The current results showed that the higher Body Mass Index (BMI), greater alpha and acetabular angles, sharp, lateral center-edge angle center-edge angle, the higher rate of a posterior wall sign, and acetabular protrusio increased the risk of OA, which support that these structural changes are major contributors to OA development.

Silicon–polyaniline–polyethylene composite films were prepared through hot pressing at a pressure of 60 MPa and different temperatures and their current–voltage characteristics were investigated. Results show that these films have varistor behavior and can be used to protect circuits from 64 V up to 80 V overvoltages. In addition, it is found that the varistor breakdown voltage decreases by increasing sintering temperature while the corresponding nonlinear coefficient increases. Dielectric properties of the films vary as a function of frequency in such a way that, at low frequencies, capacitance, relative permittivity and loss coefficient of the samples, as well as their fluctuations, are high. By increasing frequency, both dielectric properties of the films and their reduction rate decrease. On the other hand, by increasing sintering temperature, capacitance and relative permittivity of the varistors tend to increase at a constant frequency whereas their loss coefficient decreases.

In the present work, compressive strength of geopolymers produced by ordinary Portland cement, seashell powder and different alkali activators was predicted by gene expression programming design code. For constructing the models, 8 input parameters including the concentration of alkali solution, alkali binder to alkali solution weight ratio, alkali activator to cement+seashell powder weight ratio, oven curing temperature, water curing time, alkali solution type, alkali binder type and test trial number were considered. The output parameter was the compressive strength of the OPC+seashell powder based specimens. For collecting the data, 6 main factors each at 4 levels were considered for designing by the Taguchi method. A total of 32 series experiments (with 3 trials in each series) were conducted according to the L32 array proposed by the Taguchi method. According to the input parameters, the constructed models were trained and tested. From the total 96 obtained data, 70 sets were used for training and the remained 26 sets for testing the performance of the models. The results indicate that gene expression programming is a powerful tool for predicting the compressive strength of the geopolymers containing ordinary Portland cement, seashell powder and different alkali activators in the considered range with acceptable accuracy.

Background: p53 plays an important role in many areas of cellular physiology and biology, ranging from cellular development and differentiation to cell cycle arrest and apoptosis. Many of its functions are attributed to its role in assuring proper cellular division. However, since the establishment of its role in cell cycle arrest, damage repair, and apoptosis (thus also establishing its importance in cancer development), numerous reports have demonstrated additional functions of p53 in various cells. In particular, p53 appears to have important functions as it relates to neurodegeneration and synaptic plasticity. Objective: In this review, we will address p53 functions as it relates to various neurodegenerative diseases, mainly its implications in the development of HIV-associated neurocognitive disorders. Conclusion: p53 plays a pivotal role in the development of neurodegenerative diseases through its interaction with cellular factors, viral factors, and/or small RNAs that have the ability to promote the development of these diseases. Hence, inhibition of p53 may present an ideal target to restore neuronal functions.

Evapotranspiration and evaporation measurements are important parameters for many agricultural activities such as water resource management and environmental studies. There are several models which can determine pan coefficient (KPan), using wind speed, relative humidity and fetch length conditions. This paper analyses seven exiting pan models to estimate KPan values for two different climates of Iran. Monthly mean reference crop evapotranspiration (ET0) was calculated according to the pan-ET0 model. The results showed that estimated pan coefficients by majority of the suggested models were not statistically accurate to be used in the pan-ET0 conversion method. However, for the cold semi-arid climate condition, the best KPan models for estimation of ET0 were Orang and Raghuwanshi–Wallender, respectively. Also, the Snyder and Orang models were best fitted models for warm arid climate, respectively. The mean annual value of KPan, determined by Penman–Monteith FAO 56 (PMF-56) standard model for warm arid sites, was approximately 32% higher than the corresponding value in the cold semi-arid climate. Similarly, the mean annual ET0 in the warm arid sites was 66% higher, compared to the ET0 of the cold semi-arid sites. These types of warm arid and semi-arid climates are found widely throughout the world.

Transcriptional regulation of the human immunodeficiency virus type 1 (HIV-1) is a complex event that requires the cooperative action of both viral (e.g. Tat) and cellular (e.g. C/EBPβ, NF-κB) factors. The HIV-1 Tat protein recruits the human positive transcription elongation factor P-TEFb, consisting of cdk9 and cyclin T1, to the HIV-1 transactivation response (TAR) region. In the absence of TAR, Tat activates the HIV-1 long terminal repeat (LTR) through its association with several cellular factors including C/EBPβ. C/EBPβ is a member of the CCAAT/enhancer-binding protein family of transcription factors and has been shown to be a critical transcriptional regulator of HIV-1 LTR. We examined whether Tat–C/EBPβ association requires the presence of the P-TEFb complex. Using immunoprecipitation followed by Western blot, we demonstrated that C/EBPβ–cyclin T1 association requires the presence of cdk9. Further, due to its instability, cdk9 was unable to physically interact with C/EBPβ in the absence of cyclin T1 or Tat. Using kinase assays, we demonstrated that cdk9, but not a cdk9 dominant-negative mutant (cdk9-dn), phosphorylates C/EBPβ. Our functional data show that co-transfection of C/EBPβ and cdk9 leads to an increase in HIV-1 gene expression when compared to C/EBPβ alone. Addition of C/EBP homologous protein (CHOP) inhibits C/EBPβ transcriptional activity in the presence and absence of cdk9 and causes a delay in HIV-1 replication in T-cells. Together, our data suggest that Tat–C/EBPβ association is mediated through cdk9, and that phosphorylated C/EBPβ may influence AIDS progression by increasing expression of HIV-1 genes.

Expression of the viral protein R, Vpr, of HIV-1 affects many biological events in host cells including cell cycle progression, and modulates HIV-1 gene transcription. Earlier studies implicating the cellular protein p21(WAF1) (p21) in regulation of HIV-1 transcription, led us to investigate the functional and physical interaction of Vpr and p21. Our results show that Vpr modestly activated HIV-LTR in cells lacking p21 gene. Here, we describe the mechanisms by which p21 and Vpr leading to stimulation of HIV-1 transcription. Data from the protein-protein interaction experiments revealed the ability of Vpr, p21 and p300 to form a complex. Further, we show that, Vpr interacts with the N- and the C-terminal domains of p21. Furthermore, in cells expressing Vpr, p21 localizes to both the cytoplasm and the nucleus. Interestingly, expression of Vpr alleviates p21-mediated inhibition of cell departure from G1 phase. Expression of a mutant Vpr, with arginine 73 altered to serine, did not affect the ability of p21 to cause cells arrest or its sub-cellular localization. These observations reveal a new cellular partner for Vpr, and provide a new therapeutic avenue for controlling HIV-1 expression.

The principal goal of our study is to gain an insight into the representation of peripersonal space. Two different experiments were conducted in this study. In the first experiment, subjects were asked to represent principal anatomical reference planes by drawing ellipses in the sagittal, frontal and horizontal planes. The three-dimensional hand-drawing movements, which were achieved with and without visual guidance, were considered as the expression of a cognitive process per se: the peripersonal space representation for action. We measured errors in the spatial orientation of ellipses with regard to the requested reference planes. For ellipses drawn without visual guidance, with eyes open and eyes closed, orientation errors were related to the reference planes. Errors were minimal for sagittal and maximal for horizontal plane. These disparities in errors were considerably reduced when subjects drew using a visual guide. These findings imply that different planes are centrally represented, and are characterized, by different errors when subjects use a body-centered frame for performing the movement and suggest that the representation of peripersonal space may be anisotropic. However, this representation can be modified when subjects use an environment-centered reference frame to produce the movement. In the second experiment, subjects were instructed to represent, with eyes open and eyes closed, sagittal, frontal and horizontal planes by pointing to virtual targets located in these planes. Disparities in orientation errors measured for pointing were similar to those found for drawing, implying that the sensorimotor representation of reference planes was not constrained by the type of motor tasks. Moreover, arm postures measured at pointing endpoints and at comparable spatial locations in drawing are strongly correlated. These results suggest that similar patterns of errors and arm posture correlation, for drawing and pointing, can be the consequence of using a common space representation and reference frame. These findings are consistent with the assumption of an anisotropic action-related representation of peripersonal space when the movement is performed in a body-centered frame.

The Soil and Water Assessment Tool (SWAT) is a hydrologic model that was developed to predict the long-term impacts of land use change on the water balance of large catchments. Stochastic models are used to generate the daily rainfall sequences needed to conduct long-term, continuous simulations with SWAT. The objective of this study was to evaluate the performances of three daily rainfall generation models. The models evaluated were the modified Daily and Monthly Mixed (DMMm) model, skewed normal distribution (SKWD) model and modified exponential distribution (EXPD) model. The study area was the Woady Yaloak River catchment (306 km2) located in southwest Victoria, Australia. The models were assessed on their ability to preserve annual, monthly, and daily statistical characteristics of the historical rainfall and runoff. The mean annual, monthly, and daily rainfall was preserved satisfactorily by the models. The DMMm model reproduced the standard deviation of annual and monthly rainfall better than the SKWD and EXPD models. Overall, the DMMm model performed marginally better than the SKWD model at reproducing the statistical characteristics of the historical rainfall record at the various time scales. The performance of the EXPD model was found to be inferior to the performances of the DMMm and SKWD models. The models reproduced the mean annual, monthly, and daily runoff relatively well, although the DMMm and SKWD models were found to preserve these statistics marginally better than the EXPD model. None of the models managed to reproduce the standard deviation of annual, monthly, and daily runoff adequately.

Movements of different body segments may be combined in different ways to achieve the same motor goal. How this is accomplished by the nervous system was investigated by having subjects make fast pointing movements with the arm in combination with a forward bending of the trunk that was unexpectedly blocked in some trials. Subjects moved their hand above the surface of a table without vision from an initial position near the midline of the chest to remembered targets placed within the reach of the arm in either the ipsi- or contralateral workspace. In experiment 1, subjects were instructed to make fast arm movements to the target without corrections whether or not the trunk was arrested. Only minor changes were found in the hand trajectory and velocity profile in response to the trunk arrest, and these changes were seen only late in the movement. In contrast, the patterns of the interjoint coordination substantially changed in response to the trunk arrest, suggesting the presence of compensatory arm-trunk coordination minimizing the deflections from the hand trajectory regardless of whether the trunk is recruited or mechanically blocked. Changes in the arm interjoint coordination in response to the trunk arrest could be detected kinematically at a minimal latency of 50 ms. This finding suggests a rapid reflex compensatory mechanism driven by vestibular and/or proprioceptive afferent signals. In experiment 2, subjects were required, as soon as they perceived the trunk arrest, to change the hand motion to the same direction as that of the trunk. Under this instruction, subjects were able to initiate corrections only after the hand approached or reached the final position. Thus, centrally mediated compensatory corrections triggered in response to the trunk arrest were likely to occur too late to maintain the observed invariant hand trajectory in experiment 1. In experiment 3, subjects produced similar pointing movements, but to a target that moved together with the trunk. In these body-oriented pointing movements, the hand trajectories from trials in which the trunk was moving or arrested were substantially different. The same trajectories represented in a relative frame of reference moving with the trunk were virtually identical. We conclude that hand trajectory invariance can be produced in an external spatial (experiment 1) or an internal trunk-centered (experiment 3) frame of reference. The invariance in the external frame of reference is accomplished by active compensatory changes in the arm joint angles nullifying the influence of the trunk motion on the hand trajectory. We suggest that to make a transition to the internal frame of reference, control systems suppress this compensation. One of the hypotheses opened to further experimental testing is that the integration of additional (trunk) degrees of freedom into movement is based on afferent (proprioceptive, vestibular) signals stemming from the trunk motion and transmitted to the arm muscles.

The representation of the peripersonal space in humans and its modification with aging were studied by analyzing three-dimensional arm movements in healthy young and elderly adults. Participants drew ellipses in three reference planes (sagittal, frontal and horizontal), and errors in the orientation of ellipses with regard to the planes were measured. All subjects showed large disparities in the errors in different planes, errors were maximal in the horizontal plane. These findings imply that different planes are centrally represented with different errors and suggest that the mental representation of peripersonal space is anisotropic. Moreover, the elderly made larger errors than young subjects, regardless of the reference plane. Thus, the space representation is altered with aging. Compared with young adults, the elderly underestimate volume in space, a phenomenon that can be called the compression of space representation.

Muscular after-contraction (MA-C) and the ongoing postural reaction of the body was studied in standing and sitting subjects in two visual situations: eyes open or closed. EMG of trapezius and latissimus dorsalis and 3D kinematic recordings of the left scapula were analysed. The release of the long-lasting sustained isometric contraction at the level of the scapula produced a muscular after-contraction consisting of involuntary muscular contraction associated with a trunk movement similar to the unroll of a spiral. The unroll of the spiral is in the opposite direction when we compare the standing and sitting situations. We suppose that the muscular after-contraction reveals the activity of central tonigenic structures in evoking involuntary trunk movements in humans and stresses the importance of the initial postural situation (standing or sitting) and the visual condition in the characteristics of these involuntary movements.

The tumor suppressor p53 is an important cellular protein, which controls cell cycle progression. Phosphorylation is one of the mechanisms by which p53 is regulated. Here we report the interaction of p53 with another key regulator, cdk9, which together with cyclin T1 forms the positive transcription elongation complex, p-TEFb. This complex cooperates with the HIV-1 Tat protein to cause the phosphorylation of the carboxyl terminal domain (CTD) of RNA polymerase II and this facilitates the elongation of HIV-1 transcription. We demonstrate that cdk9 phosphorylates p53 on serine 392 through their direct physical interaction. Results from protein-protein interaction assays revealed that cdk9 interacts with the C-terminal domain (aa 361-393) of p53, while p53 interacts with the N-terminal domain of cdk9. Transfection and protein binding assays (EMSA and ChIP) demonstrated the ability of p53 to bind and activate the cdk9 promoter. Interestingly, cdk9 phosphorylates serine 392 of p53, which could be also phosphorylated by casein kinase II. Kinase assays demonstrated that cdk9 phosphorylates p53 independently of CKII. These studies demonstrate the existence of a feedback-loop between p53 and cdk9, pinpointing a novel mechanism by which p53 regulates the basal transcriptional machinery.

Despite the use of highly active antiretroviral therapy (HAART), neuronal cell death remains a problem that is frequently found in the brains of HIV-1-infected patients. HAART has successfully prevented many of the former end-stage complications of AIDS, however, with increased survival times, the prevalence of minor HIV-1 associated cognitive impairment appears to be rising among AIDS patients. Further, HIV-1 associated dementia (HAD) is still prevalent in treated patients as well as attenuated forms of HAD and CNS opportunistic disorders. HIV-associated cognitive impairment correlates with the increased presence in the CNS of activated, though not necessarily HIV-1-infected, microglia and CNS macrophages. This suggests that indirect mechanisms of neuronal injury and loss/death occur in HIV/AIDS as a basis for dementia since neurons are not themselves productively infected by HIV-1. In this review, we discussed the symptoms and causes leading to HAD. Outcome from this review will provide new information regarding mechanisms of neuronal loss in AIDS patients.

In order to recover balance by grasping an object for support, the CNS must rapidly move the hand toward a specific target (handhold) in the environment. The early latency (80-140 ms) of these grasping reactions would seem to preclude a role for online visual feedback in the control of the initial limb movement; however, some studies have shown that vision can influence initiation of lower-limb postural reactions at similar latency. This study explored the role of vision in controlling the initial trajectory of grasping reactions triggered by sudden unpredictable medio-lateral platform translation. Healthy young adults were instructed to recover balance by grasping a marked section of a handrail, located to their right. To reinforce a dependence on arm reactions, movement of the feet was prevented by barriers. Liquid-crystal goggles were used to occlude vision during response initiation (200 ms interval starting at perturbation onset, PO). Results showed that the initial grasping trajectory (first 100 ms) and associated muscle activation were heavily modulated to take into account the direction and speed of the perturbation-induced body motion in relation to the handrail. This modulation was unaffected by occlusion of vision at PO, indicating that information about the rail location obtained prior to PO was incorporated into the control. These findings are consistent with the view that the CNS tunes the initial arm trajectory by combining an egocentric spatial map, formed prior to PO, with online feedback about the body motion from non-visual inputs (somatosensory and/or vestibular). This prevents potential delays associated with visual processing and ensures very rapid onset of arm movement that is directed appropriately even though the position of the body is perturbed unpredictably with respect to the target.