Here, VP40 from the Ravn strain (RAVV VP40)-from a distinct Marburg virus

Wnt inhibitor clade-is demonstrated to also inhibit IFN signaling in human cells. However, neither MARV nor RAVV VP40 effectively inhibited IFN-signaling in mouse cells, as assessed by assays of the antiviral effects of IFN-alpha/beta and the IFN-alpha/beta-induced phosphorylation of Jak1, STAT1, and STAT2. In contrast, the VP40 from a mouse-adapted RAVV (maRAVV) did inhibit IFN signaling. Effective Jak1 inhibition correlated with the species from which the cells were derived and did not depend upon whether Jak1 was of human or mouse origin. Of the seven amino acid changes that accumulated in VP40 during mouse adaptation, two (V57A and T165A) are sufficient to allow efficient IFN signaling antagonism by RAVV VP40 in mouse cells. The same two changes also confer efficient IFN GSK621 manufacturer antagonist function upon MARV VP40 in mouse cells. The mouse-adaptive changes did not affect the budding of RAVV VP40 in mouse cells, suggesting that this second major function of VP40 did not undergo adaptation. These data identify an apparent determinant of RAVV host range

and virulence and define specific genetic determinants of this function.”
“Introduction: The ligand to antibody ratio is an important characteristic of a chelate/antibody conjugate. It has been widely reported that if the ratio is too high, there will be detrimental effects on immunoreactivity and biodistribution; conversely, if the ratio is too low, the radionuclide may not bind efficiently, and the stability and the specific activity will be reduced. There are little published data on the accuracy or precision of the Co-57 assay. The UK Clinical Trials Regulations state that “”systems with procedures that assure the quality

of every aspect of the trial should be implemented”". The aims of this study were to assess the reliability and accuracy of the Co-57 binding assay and validate it against defined criteria.

Method: Org 27569 Thirty-two serial assays were assessed for reliability. Two batches of conjugated antibody were also analysed by matrix-assisted laser desorption/ionisation time of flight (MALDI-TOF) mass spectrometry (MS) to allow the comparison of the functional test with a physical method.

Results: Reliability: The coefficient of variation was 0.13. Accuracy: There was 9% variation between the Co-57 binding assay and MALDI-TOF MS results.

Conclusion: A detailed method for the Co-57 ligand to antibody test is described that allows a discrete value to be obtained. The assay was validated as fit for purpose against larger values of coefficient of variation <0.20, accuracy +/- 10%, over a permissive range of 0.5-3.0 ligand to antibody ratio. (C) 2011 Elsevier Inc. All rights reserved.

Intrastriatal injection of quinolinic acid (QUIN) caused time-dependent changes (durations of 6 h, I and 7 d post-injection) in vascular remodeling. QUIN excitotoxic insult was associated with H 89 increased numbers of vessels (laminin or collagen IV markers) demonstrating considerable abnormalities in morphology, including short fragments and vascular loops. Non-lesioned striatum, with injection of phosphate buffer solution (PBS) as a vehicle, showed no

evidence for vascular remodeling. A maximal extent of vascular remodeling was measured at 1 d post-QUIN and was correlated with marked increases in microgliosis (ED1 marker) and astrogliosis (glial fibrillary acidic protein [GFAP] marker) relative to control PBS injection. Double staining of laminin with ED1 and GFAP demonstrated areas of close association of glial cells with blood vessels. Treatment of QUIN-injected animals with the anti-inflammatory compound, thalidomide significantly inhibited vascular remodeling (by 43%) and reduced microgliosis (by 33%) but was ineffective in modifying extents of astrogliosis. Intrastriatal QUIN injection was associated with a marked loss of striatal neurons relative to non-lesioned control with thalidomide treatment exhibiting a significant degree of neuroprotection (24% recovery) against

QUIN-induced neurotoxicity. These results suggest close links between microglial-mediated inflammatory responses and vascular remodeling, with inflammatory reactivity associated with, and contributing to, neuronal damage in excitotoxically-lesioned striatum. (C) 2009 IBRO. Published by Elsevier

Ltd. All rights reserved.”
“With the sequencing PLX3397 mw of the human genome and the development of new genomic technologies, biomedical discovery has been Oxymatrine transformed. The applications of these new approaches are ever-expanding from disease classification, to identification of new targets, to outcome prediction. A logical next step is the integration of genomic approaches into small molecule discovery. This review will focus on the application of genomics to compound discovery, with an emphasis on the hematological malignancies. It will focus on the use of genomic tools to discover cancer targets and the development and application of both cell-based and in silico gene expression-based approaches to small molecule discovery. Leukemia (2009) 23, 1226-1235; doi: 10.1038/leu.2009.29; published online 5 March 2009″
“Neurogenesis is a possible substrate through which antidepressants alleviate symptoms of depression. In adult male rodents and primates, chronic treatment with fluoxetine increases neurogenesis in the hippocampal formation. Little is known about the effects of the antidepressant on neurogenesis during puberty or in female animals at any age. Therefore we examined the effects of chronic fluoxetine treatment on cell proliferation and survival in male and female rats during puberty and adulthood.

Analysis of the mechanistic model of the uridyltransferase reaction suggests that the binding of this allosteric inhibitor prevents structural rearrangements that are required for the enzymatic reaction, thus providing a basis for structure-guided design of a new class of mechanism-based inhibitors of GlmU.”
“Objective: Chylothorax resulting from thoracic duct damage is often difficult to identify and repair.

GDC-0973 molecular weight We hypothesized that near-infrared fluorescent light could provide sensitive, real-time, high-resolution intraoperative imaging of thoracic duct anatomy and function.

Methods: In 16 rats, 4 potential near-infrared fluorescent lymphatic tracers were compared in terms of signal strength and imaging time: indocyanine green, the carboxylic acid of IRDye 800CW (LI-COR, Lincoln, Neb), indocyanine green adsorbed to human serum albumin, and IRDye 800CW conjugated covalently to human serum albumin. Optimal agent was validated in 8 pigs approaching human size (n = 6 by open surgery with FLARE imaging system [Beth Israel Deaconess Medical Center, Boston, Mass] and n 2 by video-assisted thoracoscopic surgery minimally invasive [m-FLARE] imaging system [Beth Israel Deaconess Medical Center]). Lymphatic tracer injection site, dose, and timing were optimized.

Results: For signal strength, sustained imaging time, and clinical translatability, the best lymphatic tracer was indocyanine green, which is already

Food and Drug Administration approved for other indications. Selleckchem Sepantronium In pigs, a simple subcutaneous injection of indocyanine green into lower leg (>36 mu g/kg), provided thoracic duct imaging with onset of about 5 minutes after injection, sustained imaging for at least 60 minutes after injection, and signal-to-background

ratio of at least 2. With this technology, normal thoracic duct flow, collateral flow, injury models, and repair models could all be observed under direct visualization.

Conclusions: Near-infrared fluorescent light could provide sensitive, sustained, real-time imaging of thoracic duct anatomy and function during both open and video-assisted thoracoscopic surgery Resveratrol in animal models. (J Thorac Cardiovasc Surg 2011;142:31-8)”
“BACKGROUND

Approximately 2 million people participate in long-distance running races in the United States annually. Reports of race-related cardiac arrests have generated concern about the safety of this activity.

METHODS

We assessed the incidence and outcomes of cardiac arrest associated with marathon and half-marathon races in the United States from January 1, 2000, to May 31, 2010. We determined the clinical characteristics of the arrests by interviewing survivors and the next of kin of nonsurvivors, reviewing medical records, and analyzing postmortem data.

RESULTS

Of 10.9 million runners, 59 (mean [+/-SD] age, 42+/-13 years; 51 men) had cardiac arrest (incidence rate, 0.54 per 100,000 participants; 95% confidence interval [CI], 0.41 to 0.70).

Results: Twenty-three studies satisfied the inclusion criteria. Preoperative

QOL in AAA patients has been previously suggested as being worse than that of the general population, that OR patients have a worse QOL in the early postoperative period, and that EVAR patients have a worse QOL in the longer term. None of these assertions is uniformly PF-04929113 supplier supported in the literature. From the existing evidence, no clear conclusions can be drawn about the relative QOL benefits of OR vs EVAR.

Conclusions: There are a paucity of good-quality data relating to health status and QOL in patients undergoing AAA repair. Little is known about the prevalence of preoperative or postoperative symptoms and the degree to which these influence patient well-being. Further investigation is needed to clarify health status and QOL changes in these patients and allow clinicians to make targeted improvements in practice. (J Vasc Surg 2012;56:520-7.)”
“Wheat (Triticum aestivum L.) is a staple food selleck for half of the world. Its productivity and agronomical practices, especially for nitrogen supplementation, is governed by the nitrogen efficiency (NE) of the genotypes.

We analyzed 16 popular cultivated Indian varieties of wheat for their NE and variability estimates using a set of 21 simple sequence repeat (SSR) markers, derived from each wheat chromosome. These genotypes were categorized into three groups, viz., low, moderate, and high nitrogen efficient. Of these 16 genotypes, we have reported six, eight, and two genotypes in high, moderate, and low NE categories, respectively. The differential NE in these genotypes was supported by nitrogen uptake and assimilation parameters. The values of average polymorphic information content and marker index for these SSR markers were estimated to be 0.32 and 0.59, respectively. The genetic similarity coefficient for all possible pairs of varieties SDHB ranged from 0.41 to 0.76, indicating the presence of considerable range of genetic diversity at molecular level. The dendrogram prepared on the basis of unweighted pair-group method of arithmetic average algorithm grouped the 16 wheat varieties into three major clusters. The clustering

was strongly supported by high bootstrap values. The distribution of the varieties in different clusters and subclusters appeared to be related to their variability in NE parameter that was scored. Genetically diverse parents were identified that could potentially be used for their desirable characteristics in breeding programs for improvement of NE in wheat.”
“The past decade has seen the beginning of a revolution in the way in which surgeons learn their craft. As technology has become increasingly sophisticated, and care more accountable, traditional methods of skill acquisition are no longer optimal as sole training modalities. Against this backdrop, there has been a shift toward competency-based training programs reflecting the growing emphasis on outcomes-based medical education.

In general, a 3-log difference was observed between the L/D microscopy count and culture count accounting for the presence of non-culturable fraction in the bacterial population in in-use MWF.

Conclusions: The optimized AR staining- and the L/D staining-based microscopy methods have the potential for rapid, specific and differential assessment (viable vs non-viable) of MWF-associated mycobacteria and co-contaminants in field MWF.

Significance and Impact of the study: Early detection of MWF mycobacteria by rapid, low-cost, less-skill intensive and culture-independent fluorescence-based microscopy methods SGC-CBP30 datasheet will facilitate timely intervention to protect the machine workers from occupational hazards.”
“Aim: To estimate

the ethylene diamine tetraacetic acid

(EDTA) concentration at which the L1 enzyme activity in the cell extracts of Stenotrophomonas maltophilia can be mostly inhibited.

Methods and Results: The effective inhibition concentration of EDTA against the L1 enzyme in the cell extracts was firstly evaluated by using the L2 isogenic mutant of S. maltophilia KJ, KJ Delta L2, as the assayed strain. Approximately 92% L1 activity was inhibited by 10 mmol l(-1) EDTA, which is 100-fold higher than that from previously reported protocols (0.1 mmol l(-1)). Three phylogenetic clusters of L1 proteins were revealed from 11 clinical S. maltophilia isolates, with a L1 protein divergence of 0-11%. The EDTA concentration required to inhibit the L1 enzymes of different phylogenetic clusters was estimated to be 10 mmol l(-1).

Conclusion: Thiazovivin in vivo The previous nitrocefin-EDTA protocol for differentially quantifying the L1 and L2 activity in the cell extracts has been modified by raising the added EDTA concentration to 10 mmol l(-1).

Significance and Impact of the Study: A rapid and accurate method for determination of L1 and L2 activity will provide a convenient tool for enzyme characterization and induction mechanism study of S. maltophilia.”
“Aims: To detect sensor histidine protein kinases (HPKs) similar to accessory gene regulator C (AgrC) from the rumen microbial ecosystem.

Methods and the Results: Genes

related to sensor HPKs were amplified by PCR using two pairs of oxyclozanide agrC-specfic primers from DNA extracted from bovine rumen contents. The PCR products were cloned, sequenced and phylogenetically analysed. It appeared that two sequences were HPKs.

Conclusions: Although amino acid sequences deduced from the nucleotide sequences obtained in this study showed high similarities with sensor HPKs responding to citrate or C-4-dicarboxylates, they did not show high similarities with AgrC. Significance and Impact of the Study: This study revealed the presence in the rumen of sensor HPKs responding to citrate or C-4-dicarboxylates, which could stimulate rumen fermentation. Therefore, it has been shown that citrate or C-4-dicarboxylate metabolism is partially regulated by a two-component regulatory system in some rumen bacteria.

Intrathecal injection of non-amidated phoenixin (2.5 mu g) did not significantly alter the number of writhes selleck kinase inhibitor evoked by acetic acid. Our result shows that phoenixin is expressed in sensory neurons of the dorsal root, nodose and trigeminal ganglia, the amidated peptide is bio- active, and exogenously administered phoenixin may preferentially suppress visceral as opposed to thermal pain. (C) 2013 IBRO. Published

by Elsevier Ltd. All rights reserved.”
“Certain immune-driven mutations in HIV-1, such as those arising in p24(Gag), decrease viral replicative capacity. However, the intersubtype differences in the replicative consequences of such mutations have not been explored. In HIV-1 subtype B, the p24(Gag) M250I mutation is a rare variant (0.6%) that is enriched among elite controllers (7.2%) (P = 0.0005) and appears to be a rare escape variant selected by HLA-B58 supertype alleles (P < 0.01). In contrast, in subtype C, it is a relatively common minor polymorphic variant (10 to 15%) whose appearance is not associated with a particular HLA allele. Using site-directed mutant viruses, we demonstrate

that M250I reduces in vitro viral replicative capacity in both subtype B and subtype C sequences. However, whereas in subtype C downstream compensatory mutations at p24(Gag) codons 252 and 260 reduce the adverse effects of M250I, fitness costs in subtype B appear difficult to restore. Indeed, patient-derived subtype B sequences harboring M250I exhibited in vitro replicative defects, while those Quisqualic acid from subtype C did not. The structural implications of M250I were predicted

by protein modeling to be greater in subtype B versus C, providing a potential explanation this website for its lower frequency and enhanced replicative defects in subtype B. In addition to accounting for genetic differences between HIV-1 subtypes, the design of cytotoxic-T-lymphocyte-based vaccines may need to account for differential effects of host-driven viral evolution on viral fitness.”
“Objective: To explore relationships between wake-and sleep-related health behaviors and circulating concentrations of inflammatory markers (interleukin [IL]-6 and tumor necrosis factor [TNF]-alpha) in a cohort of community dwelling older adults. Low-grade chronic inflammation is an important risk factor for age-related morbidity. Health behaviors, including average aggregate measures of sleep, have been linked to increased inflammation in older adults. Variability in sleep timing may also be associated with increased inflammation. Method: Participants were community dwelling older adults >= 60 years (n = 222: 39 bereaved, 55 caregivers, 52 with insomnia, and 76 good sleepers). Mean values and intraindividual variability in sleep, as well as caffeine and alcohol use, exercise, and daytime napping, were assessed by sleep diaries. Blood samples were obtained in the morning. Results: Several interactions were noted between sleep behaviors, inflammatory markers, and participant group.

BSA which acts as an efficient blocking layer in microarrays, tends to show an interaction with QDs. In view of this fact, we investigated two series of samples which were fabricated in the presence and absence of BSA blocking layer. Variation selleck kinase inhibitor in the incubation time required for the antigen-antibody interaction to take place, different proteins as controls and the effect of bare QDs on these microarrays, were the three main parameters which

were studied in these two series. Samples fabricated in the absence of BSA blocking layer exhibited an extremely high specificity in the detection of cancer proteins and were also marked by negligible nonspecific binding effects of QDs, in stark contrast to the samples fabricated using BSA as a blocking layer. Fabrication of nanoarrays of QD-conjugated PSA Abs having a spot size of nearly 900 nm has also been demonstrated. www.selleckchem.com/products/Bortezomib.html Thus, we show the potential offered by QDs in in vitro analysis of cancer biomarker imaging.”
“Although neuroimmune interactions associated with the development of pain sensitization in models of neuropathic pain have been widely studied, there are some aspects that require further investigation. Thus, we aimed to evaluate whether the local intraneural or perineural injections of dexamethasone, an efficacious anti-inflammatory

and immunosuppressant drug, delays the development of both thermal hyperalgesia and mechanical allodynia in an experimental model of neuropathic pain in rats. Hargreaves and electronic von Frey tests were applied. The chronic constriction injury (CCI) of right sciatic nerve was performed. Single intraneural dexamethasone administration at the moment of constriction delayed the development of sensitization

for thermal hyperalgesia and mechanical allodynia. Baf-A1 price However, perineural administration of dexamethasone, at the highest dose, did not delay experimental pain development. These results show that inflammation/immune response at the site of nerve lesion is an essential trigger for the pathological changes that lead to both hyperalgesia and allodynia. In conclusion, this approach opens new opportunities to study cellular and molecular neuroimmune interactions associated with the development of pain derived from peripheral neuropathies. (C) 2012 Elsevier Ireland Ltd. All rights reserved.”
“Vesicular stomatitis virus (VSV), a prototype of the Rhabdoviridae family, contains a single surface glycoprotein (G) that is responsible for attachment to cells and mediates membrane fusion. Working with the Indiana serotype of VSV, we employed a reverse genetic approach to produce fully authentic recombinant viral particles bearing lethal mutations in the G gene. By altering the hydrophobicity of the two fusion loops within G, we produced a panel of mutants, W72A, Y73A, Y116A, and A117F, that were nonfusogenic.

Results. – One hundred and eight patients (mean age 47.7 years, 55% men) were consecutively enrolled. Sensory loss in the painful dermatonne was the most frequent finding at physical examination Vemurafenib solubility dmso (56% of cases). EMG was abnormal in at least one muscle supplied by femoral and sciatic nerves in 45 cases (42%). Inclusion of paraspinal muscles increased sensitivity to only 49% and that of proximal muscles was useless. Motor and sensory neurography was seldom

abnormal. The most frequent motor neurographic abnormalities were a delay of F-wave minimum latency and decrease in the compound muscle action potential amplitude from extensor digitorum brevis and abductor hallucis in L5 and S1 radiculopathies, respectively. Sensory neurography was usually normal, the amplitude of sensory nerve action potential was seldom reduced when HD injured dorsal root ganglion or postganglionic root fibres. Multivariate logistic regression analysis showed that EMG abnormalities could be predicted by myotomal muscular weakness, abnormal deep reflexes, and paraesthesiae. The only clinical and electrophysiological differences with respect to root involvement level concerned deep reflexes and motor neurography of deep peroneal and tibial nerves.

Conclusions. – Only some EDX parameters are helpful for the diagnosis of lumbosacral radiculopathy.

EMG was abnormal in less than 50% of cases and its abnormalities could be predicted by some clinical findings. However, neurography is useful as a GSK461364 tool for differential diagnosis between radiculopathy and more diffuse disorders of the peripheral nervous system (polyneuropathy, plexopathy). (C) 2013 Elsevier Masson SAS. All rights reserved.”
“Recent findings from several large-scale community surveys suggest that delusions tend to occur in non-clinical samples as a continuous phenotype rather than as an all-or-none phenomenon. However, the

majority of studies on the prevalence of delusions and paranoid ideation are limited to Western samples. The present study aims to examine the phenomenon and base-rate of paranoid ideation in a Chinese non-clinical sample. A total of 4951 undergraduates (65.9% male) completed a checklist for paranoid ideation and the Schizotypal Personality Questionnaire (SPQ). Participants Rebamipide were classified into individuals with and without schizotypal personality disorder (SPD) features based on the SPQ. For the frequency subscale, 2.1-18.2% of the participants without SPD features experienced certain types of paranoid ideation at least once a week during the survey. The prevalence rate even elevated to a higher proportion in conviction and distress dimensions. For the conviction subscale, 93-53.5% of the participants somewhat believed of the ideations. For the distress subscale, 14.7-31.3% of the participants felt somewhat distressing in the experienced paranoid ideation.

The results

indicate that Ca2+ imaging is a useful tool to quantify the amount of neuronal gap junction coupling in cultures.(C) 2008 Elsevier Ireland Ltd. All rights reserved.”
“The vaccinia virus I5L open reading frame encodes a 79-amino-acid protein, with two predicted transmembrane domains, that is conserved among all sequenced members of the chordopoxvirus subfamily. No nonpoxvirus homologs or functional motifs have been recognized, and the role of the I5 protein remains unknown. We found that synthesis of I5 was dependent on viral DNA replication and occurred MLN0128 exclusively at late times, consistent with a consensus late promoter motif adjacent to the start of the open reading frame. I5 was present in preparations of purified virions and could be extracted with nonionic detergent, suggesting membrane insertion. Transmission electron microscopy of immunogold-labeled thawed cryosections of infected cells

revealed the association of an epitope-tagged I5 with the membranes of immature and mature virions. Viable I5L deletion and frameshift mutants were constructed and found to replicate like wild-type virus in a variety of cell lines and primary human epidermal keratinocytes, indicating that the protein was dispensable for in vitro cultivation. However, mouse intranasal challenge experiments indicated that MM-102 a mutant virus with a frameshift resulting in a stop codon near the N terminus of I5 was attenuated compared

to control virus. The attenuation was correlated with clearance of mutant viruses from the respiratory tract and with less progression and earlier resolution Dichloromethane dehalogenase of pathological changes. We suggest that I5 is involved in an aspect of host defense that is evolutionarily conserved although a role in cell tropism should also be considered.”
“In a previous study of experimental murine encephalitis induced by Junin virus (JV), an arenavirus, we showed increased expression of iNOS by unidentified cells, concomitant with the astrocyte reaction. The specific inhibition of iNOS was associated with greater mortality but lower astrocytosis, suggesting that the protective role of nitric oxide (NO) synthesized by iNOS was related to enhanced astrocyte activation, representing a beneficial cellular response to virus-induced central nervous system damage. In the present work, cultured astrocytes were used to study whether JV infection could trigger iNOS expression and assess its eventual relationship with viral replication, glial fibrilary acidic protein (GFAP) expression levels and the presence of apoptosis. We found that JV infection of astrocytes did not induce apoptosis but produced both increased iNOS synthesis, detected by immunocytochemistry and fluorescence activated cell sorting (FACS) analysis, and increased NO, which was indirectly measured by nitrite/nitrate levels.

Fluoxetine and ECT significantly increased mGlu(7) receptor expression in NS animals. This work demonstrates changes to mGlu(4) receptor expression may be a lasting molecular change which occurs due to early-life stress. Taken together our data shows there are selective changes to group III mGlu receptors under basal and early-life stress conditions.

This article is part of a Special Issue entitled ‘Metabotropic

Glutamate Receptors’. (c) 2012 Elsevier Ltd. All rights reserved.”
“Aim: To determine the prevalence and sequelae of falls in PBC and to identify modifiable risk factors.

Design: Cross-sectional, geographical, population census of PBC and two control groups: SP600125 primary sclerosing cholangitis and a community dwelling population. Multidisciplinary falls assessment of a representative group of PBC.

Methods: Symptom assessment tools, completed by the

three cohorts, determined the prevalence of falls, injuries and associated symptoms. Multidisciplinary assessments, adhering to NICE PX-478 datasheet guidelines, identified modifiable fall associations.

Results: Significantly more of the PBC population had fallen (72% P < 0.001) than both control groups. Fifty-five percent had fallen in the last year (P < 0.001), and 22% more than once in the last year (P < 0.01). Seventy percent of PBC fallers were injured, 27% fractured a bone and 19% were admitted to hospital, all significantly more common than controls. Postural dizziness was significantly worse in fallers (P < 0.001), as were balance (P < 0.001) and lower limb strength (P = 0.002). Lower limb strength was independently associated with number of falls in previous year (beta = 0.184, P < 0.001).

Conclusion: Falls and resultant injury are prevalent in PBC and more common than previously recognized. Addressing postural dizziness, poor balance

and lower limb weakness using a multidisciplinary approach has the potential to reduce falls, morbidity and mortality and as a result improve quality of life.”
“A fundamental question relating to animal behaviour is how animals learn; in particular, how they come to associate stimuli with rewards. Numerous empirical findings can be explained by assuming that animals use some mechanism similar to the Rescorla-Wagner learning rule, which is a relatively simple and highly general method of updating the associative cAMP strength between different stimuli. However, the Rescorla-Wagner rule is often not optimal, which raises the question of why a rule with such properties should have evolved. We consider the evolution of learning rules in a simple environment where there exists an optimal rule of similar complexity to the Rescorla-Wagner rule. We show that because the Rescorla-Wagner rule is less sensitive to changes in its parameters than the optimal rule, there is a wider range of parameter values over which the rule structure is initially viable.