We experimentally evaluate the performance of our method CCiMFP on yeast PPI networks. Using gold standard sets of protein complexes, Gene Ontology (GO), and localization annotations, we show that our method gains an improvement over the previous algorithms in terms of precision, recall, and biological significance Selleckchem JNJ-26481585 of the predicted complexes. The colocalization scores of our predicted

complex sets are higher than those of two known complex sets. Moreover, our method can detect GO-enriched complexes with disconnected cores compared with other methods based on the subgraph connectivity.”
“Purpose: Laparoscopic pyeloplasty and open pyeloplasty have comparable efficacy for ureteropelvic junction obstruction in pediatric patients. The role of laparoscopic pyeloplasty in infants is less well defined. We present our updated experience with laparoscopic pyeloplasty in children younger than 1 year.

Materials and Methods: We retrospectively reviewed

the records of all 29 infants treated with transperitoneal laparoscopic pyeloplasty for symptomatic and/or radiographic ureteropelvic junction obstruction from May 2005 to February 2012. Patients were followed with renal ultrasound at regular intervals. Treatment failure was defined as the inability to complete A-1331852 purchase the intended procedure, persistent radiographic evidence of obstruction and/or the need for definitive Bcl-w adjunctive procedures.

Results: Transperitoneal laparoscopic pyeloplasty was performed in 29 infants 2 to 11 months old (mean age 6.0 months) weighing 4.1 to 10.9 kg (mean +/- SD 7.9 +/- 1.6). Followup was available in all except 5 patients (median 13.9 months, IQR 7.7-23.8). Mean operative time was 245 +/- 44 minutes. All cases were completed laparoscopically. Three postoperative complications were reported, including

ileus, superficial wound infection and pyelonephritis. Two patients had persistent symptomatic and/or radiographic evidence of obstruction, and required reoperative pyeloplasty. The overall success rate was 92%.

Conclusions: Laparoscopic pyeloplasty in infants remains a technically challenging procedure limited to select centers. Our early experience revealed a success rate comparable to that of other treatment modalities with minimal morbidity.”
“Recent high-throughput experiments have generated protein-protein interaction data on a genomic scale, yielding the complete interactome for several organisms. Various graph clustering algorithms have been applied to protein interaction networks for identifying protein complexes and functional modules. Although the previous algorithms are scalable and robust, their accuracy is still limited because of the complex connectivity found in protein interaction networks. In this study, we propose a novel information-theoretic definition, graph entropy, as a measure of the structural complexity of a graph.

However, precise localization of PRUNE2 in the brain remains unclear. Here, we identified the distribution of Prune2 mRNA in the adult mouse brain. Prune2 mRNA is predominantly expressed in the neurons of the cranial nerve motor nuclei and the motor neurons of the spinal cord. The expression in the dorsal root ganglia

(DRG) is consistent with the previously described reports. In addition, we observed the expression in another sensory Q-VD-Oph research buy neuron in the mesencephalic trigeminal nucleus. These results suggest that Prune2 may be functional in these restricted brain regions. (C) 2011 Elsevier Ireland Ltd. All rights reserved.”
“Objective: Surgical site infections after cardiothoracic surgery substantially increase the risk for illness, mortality, and costs. Surveillance of surgical site infections might assist in the prevention of these infections. This study describes the Dutch surveillance methods and results of data collected between 2002 and 2007.

Methods: Three cardiothoracic procedures were included: coronary artery Fosbretabulin bypass graft procedures, valve surgery, and a combination of coronary artery bypass graft procedures with concomitant valve surgery. The surgical site infections were divided into sternal and harvest-site infections. Postdischarge

surveillance of surgical site infections was mandatory for sternal wounds and elective for harvest-site wounds, with a follow-up period of 42 postoperative days. Multivariate logistic regression was used for risk factor analysis of coronary artery bypass grafts, with adjustment for random variation among hospitals.

Results: Eight of the 16 Dutch cardiothoracic centers participated and collected data

on 4066 procedures and 183 surgical site infections, new revealing a surgical site infection rate of 2.4% for sternal wounds and 3.2% for harvest sites. Sixty-one percent of all surgical site infections were recorded after discharge. For sternal surgical site infections after coronary artery bypass graft procedures, the significant risk factors were rethoracotomy, diabetes, preoperative length of stay, and obesity; for harvest-site infections, the most relevant risk factor was a long time on extracorporeal circulation. Adjusted surgical site infection rates regarding coronary artery bypass graft procedures varied between hospitals from 0.0% to 9.7%.

Conclusions: Large differences were found in surgical site infection rates between Dutch hospitals, which indicate room for improvement. The follow-up of patients after hospital discharge reduces underestimation of surgical site infection rates.

Many theories of vision have been premised on the central role played by prediction. Yet, implicit prediction in human vision has been difficult to assess in the laboratory, and many results have not distinguished between the indisputably important role of memory and the future-oriented aspect of prediction. Now, a new and unexpected

MK5108 purchase finding – that humans can resume an interrupted visual search much faster than they can start a new search – offers new hope, because the rapid resumption of a search seems to depend on participants forming an implicit prediction of what they will see after the interruption. These findings combined with results of recent neurophysiology studies provide a framework for studying implicit prediction in perception.”
“The optimized expression of recombinant Potato virus A coat protein (ACP) carrying two different epitopes from Human papillomavirus type 16 (HPV16) was developed. Epitope derived from minor capsid protein L2 was expressed as N-terminal fusion with ACP while an epitope derived from E7 oncoprotein was fused selleck to its C-terminus. The construct was cloned into Potato

X potexvirus (PVX) based vector and transiently expressed in plants using Agrobacterium tumefaciens mediated inoculation.

To increase the level of expressed protein the transgenic Nicotiana benthamiana plants expressing Potato virus A HC-Pro gene and transgenic Nicotiana tabacum, cv. Petit Havana SR1 carrying Potato virus A P3 protein gene were tested. Synergistic infection of host plants with PVX carrying the construct and Potato virus Y-o (PVYO) increased the expression of L2ACPE7 in N. tabacum and in transgenic N. benthamiana carrying potyviral HC-Pro gene as compared to control plants infected with L2ACPE7 only. (c) 2007 Elsevier Inc. All rights reserved.”
“Upregulation of cytokines and chemokines is a frequent finding in multiple myeloma (MM). CCL3 (also 17-DMAG (Alvespimycin) HCl known as MIP-1 alpha) is a pro-inflammatory chemokine, levels of which in the MM microenvironment correlate with osteolytic lesions and tumor burden. CCL3 and its receptors, CCR1 and CCR5, contribute to the development of bone disease in MM by supporting

tumor growth and regulating osteoclast (OC) differentiation. In this study, we identify inhibition of osteoblast (OB) function as an additional pathogenic mechanism in CCL3-induced bone disease. MM-derived and exogenous CCL3 represses mineralization and osteocalcin production by primary human bone marrow stromal cells and HS27A cells. Our results suggest that CCL3 effects on OBs are mediated by ERK activation and subsequent downregulation of the osteogenic transcription factor osterix. CCR1 inhibition reduced ERK phosphorylation and restored both osterix and osteocalcin expression in the presence of CCL3. Finally, treating SCID-hu mice with a small molecule CCR1 inhibitor suggests an upregulation of osteocalcin expression along with OC downregulation.

In the present study,

the reciprocal neuronal networks in the elder group were compared with the young group to investigate the differences of the intrinsic brain activity using a method of temporal buy JPH203 correlation analysis based on seed regions of posterior cingulate cortex (PCC) and ventromedial prefrontal cortex (vmPFC). We found significant decreased positive correlations and negative correlations with the seeds of PCC and vmPFC in the old group. The decreased coactivations in the DMN network components and their negative networks in the old group may reflect age-related alterations in various brain functions such as attention, motor control and inhibition modulation in cognitive processing. These alterations

in the resting state anti-correlative networks could provide neuronal substrates for the aging brain. (C) 2011 Elsevier Ireland Ltd. All rights reserved.”
“Background. Increasingly, researchers have begun to explore the association between depression and mortality. The current study examined the association between depressive symptoms and all-cause and cause-specific mortality in Chinese older people. Further to examine whether any associations were similar by sex and health status.

Methods. We used the Chinese version of the 15-item Geriatric Depression Scale to measure depressive symptoms (Geriatric Depression Scale score >= 8) and Cox regression to examine the association with all-cause and cause-specific mortality in a population-based cohort study of all 56.088 enrollees, aged 65 years or older, from July 1998 to December 2000 at Combretastatin A4 datasheet all 18 Elderly Health Centers of Department of Health

of Hong Kong. The cohort was followed up for mortality till December 31, 2005.

Results. Depressive symptoms were associated with all-cause mortality (hazard ratio 1.21, 95% confidence interval: 1.08-1.37) in men only (p value for sex interaction <.05) and with suicide mortality ZD1839 molecular weight in men (hazard ratio 2.81, 95% confidence interval: 1.13-7.01) and women (hazard ratio 2.40, 95% confidence interval: 1.18-4.82) but not with other major causes of death after adjusting for age, education, monthly expenditure, smoking, alcohol drinking, physical activity, body mass index, health status, and self-rated health. The associations did not vary with health status.

Conclusions. Depressive symptoms were associated with all-cause mortality in men and with suicide in both sexes. Randomized controlled trials concerning the effects of treatment of depression on mortality are needed to clarify the causal pathways.”
“We recently reported that young adults (YA) preferentially recruit cerebellar lobule HVI for symbolic motor sequence learning [3]. Learning magnitude in the symbolic condition was correlated with activation level in lobule HVI. Here, we evaluated age differences in the symbolic representation of motor sequence learning.

This revised network

model of the limbic system reconciles recent functional imaging findings with anatomical accounts of clinical disorders commonly associated with limbic pathology. (C) 2013 Elsevier Ltd. All rights reserved.”
“Influenza has been circulating in the human population and has caused three pandemics in the last century (1918 H1N1, 1957 H2N2 and 1968 H3N2). The 2009 A(H1N1) MM-102 cell line was classified by World Health Organization as the fourth pandemic. Influenza has a high evolution rate, which makes vaccine design challenging. We here consider an approach for early detection of new dominant strains. By clustering the 2009 A(H1N1) sequence data, we found two main clusters. We then define a metric to detect the emergence of dominant strains. We show on historical H3N2 data that this method is able to identify a cluster around an incipient dominant strain before it becomes dominant. For example, for H3N2 as of 30 March 2009, the method detects the cluster for the new A/British Columbia/RV1222/2009 strain. This strain detection tool would appear to be useful for annual influenza vaccine selection.”
“Individual differences are a hallmark of drug addiction. Here,

we describe a rat model based on differential initial responsiveness to low dose cocaine. Despite similar brain cocaine levels, individual outbred Sprague-Dawley rats exhibit markedly different magnitudes of acute cocaine-induced locomotor activity and, thereby, can be classified as low or high cocaine responders (LCRs or HCRs). LCRs Pictilisib chemical structure and HCRs differ in drug-induced, but not novelty-associated, hyperactivity. LCRs have higher basal numbers of striatal dopamine transporters Amobarbital (DATs) than HCRs and exhibit marginal cocaine

inhibition of in vivo DAT activity and cocaine-induced increases in extracellular DA. Importantly, lower initial cocaine response predicts greater locomotor sensitization, conditioned place preference and greater motivation to self-administer cocaine following low dose acquisition. Further, outbred Long-Evans rats classified as LCRs, versus HCRs, are more sensitive to cocaine’s discriminative stimulus effects. Overall, results to date with the LCR/HCR model underscore the contribution of striatal DATs to individual differences in initial cocaine responsiveness and the value of assessing the influence of initial drug response on subsequent expression of addiction-like behaviors. (C) 2013 Elsevier Ltd. All rights reserved.”
“In this study, three lines of evidence suggest a role for alpha(2)-adrenoreceptors in rat pup odor-preference learning: olfactory bulb infusions of the alpha(2)-antagonist, yohimbine, prevents learning; the alpha(2)-agonist, clonidine, paired with odor, induces learning; and subthreshold clonidine paired with subthreshold beta-adrenoceptor activation also recruits learning. Increased mitral cell layer pCREB occurs with clonidine-infusion, but cAMP is not increased.

Two patients with chordoma relapsed; 1 died of disease, and the other was alive with disease. Two patients with metastasis died of multiple remote metastases. No evidence of local recurrence was found in the other patients.

CONCLUSION: The anterior retropharyngeal approach is a favorable route to treat tumor lesions of the C2 vertebral body that allows tumor resection and placement of anterior constructs MG-132 molecular weight between C1 and the subaxial vertebral body. Tumor resection and 2-column reconstruction could safely be accomplished simultaneously through the combined

anterior retropharyngeal-posterior approach.”
“Stroke is a common, serious, and disabling global health-care problem, and rehabilitation is a major part of patient care. There is evidence to support rehabilitation

in well coordinated multidisciplinary stroke units or through provision of early supported provision of discharge teams. Potentially beneficial treatment options for motor recovery of the arm include constraint-induced movement therapy and robotics. Promising interventions that could be beneficial to improve aspects of gait include fitness training, high-intensity therapy, and repetitive-task training. Repetitive-task training might also improve transfer functions. Occupational therapy can improve activities of daily living; however, information about the clinical effect of Transmembrane Transporters activator various strategies of cognitive rehabilitation and strategies for aphasia and dysarthria is scarce. Several large trials of rehabilitation practice and of novel therapies (eg, stem-cell therapy, repetitive transcranial magnetic stimulation, virtual reality, robotic

therapies, and drug augmentation) are underway to inform future practice.”
“BACKGROUND: Supra Y-27632 2HCl orbital frontal minicraniotomy is one of the most commonly used minimally invasive approaches for anterior cranial fossa lesions.

OBJECTIVE: To describe our experience with the transpalpebral “”eyelid”" incision to obtain access to the anterior cranial fossa.

METHODS: We describe the approach and technique of the transpalpebral eyelid incision in a step-by-step fashion and discuss the results of 40 cases for which the eyelid incision was used. We retrospectively reviewed the charts of these patients to analyze outcomes with regard to opening and closing time, length of hospital stay, residual aneurysm or Simpson grade for resection, complications, and cosmetic result.

RESULTS: We treated 31 anterior circulation aneurysms (28 unruptured and 3 ruptured), 7 anterior skull base meningiomas, 1 frontal low-grade glioma, and 1 frontal cavernoma using the transpalpebral incision. Opening time was about 45 to 60 minutes, and closure time from dura to skin was about 45 to 60 minutes. The hospital length of stay was similar to that in our open craniotomy cases. No residual aneurysm was demonstrated in the follow-up studies of all 31 aneurysms. Simpson grade I resection was achieved in 6 meningiomas.

6-OHDA showed similar toxicity pattern in differentiated compared to undifferentiated NPCs. By evaluating the toxicity of MPP+ on MAP2ab(+) neurons derived from both mNPCs and sNPCs as well as tyrosine hydroxylase (TH)(+) dopaminergic cells from mNPCs, we found concentration-dependent cell death of all cell types with no increased vulnerability of TH+ cells. Primary TH+ neurons showed significantly higher vulnerability to MPP+. Together, we demonstrated stage-dependent vulnerability of NPCs towards dopaminergic neurotoxins,

but no selective vulnerability of NPC-derived TH+ dopaminergic cells towards MPP+. This cell system seems not suitable as a screening tool for selective dopaminergic toxicity. (C) 2008 Elsevier Inc. All rights reserved.”
“Sulfatide is abundantly expressed in various mammalian organs, including the intestines and trachea, in see more which influenza A viruses (IAVs) replicate. However, the function of sulfatide in IAV infection remains unknown. Sulfatide is synthesized by two transferases, ceramide galactosyltransferase (CGT) and cerebroside sulfotransferase (CST), and is degraded by arylsulfatase A (ASA). In this study, we demonstrated that sulfatide enhanced click here IAV replication through efficient translocation of the newly synthesized IAV nucleoprotein

(NP) from the nucleus to the cytoplasm, by using genetically produced cells in which sulfatide expression was down-regulated by RNA interference against CST mRNA or overexpression of the ASA gene and in which sulfatide expression was up-regulated by overexpression of both the CST and CGT genes. Treatment of IAV-infected cells with an antisulfatide monoclonal antibody (MAb) or an anti-hemagglutinin (HA) MAb, which

blocks the binding of IAV and sulfatide, resulted in a significant reduction in IAV replication and accumulation of the viral NP in the nucleus. Furthermore, antisulfatide MAb protected mice against lethal challenge Uroporphyrinogen III synthase with pathogenic influenza A/WSN/33 (H1N1) virus. These results indicate that association of sulfatide with HA delivered to the cell surface induces translocation of the newly synthesized IAV ribonucleoprotein complexes from the nucleus to the cytoplasm. Our findings provide new insights into IAV replication and suggest new therapeutic strategies.”
“Previous studies have suggested that prenatal exposure to nicotine is associated with abnormal development in fetuses, including fetal brain damage. The present study determined the effect of maternal administration of nicotine during different gestational periods on brain nicotine receptor subunits in fetal rats. Subcutaneous injections of nicotine in maternal rats from the early and middle gestation decreased fetal blood PO2, increased fetal blood PCO2 and hemoglobin, and decreased fetal brain weight. The nicotinic acetylcholine receptor (nAChRs) mRNA abundance in the fetal brain was significantly changed by prenatal treatment with nicotine during pregnancy.

Finally, in sections of injured sciatic nerves, we analyzed the expression of Cdc2 and GAP-43 proteins that are both up-regulated during peripheral regenerative processes. Compared to mice subjected to long-lasting

treadmill running, mice subjected to short-lasting treadmill running showed an acceleration of the regenerative processes at the injured sciatic nerve. Our data demonstrate that short-lasting treadmill running, by reducing the neuropathic pain symptoms and facilitating the ISRIB molecular weight regenerative processes of the injured nerve, have beneficial rehabilitative effects on the functional recovery after peripheral nerve injury. (C) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.”
“Aims:

To verify the specificity of a PCR assay for the identification and diagnosis of Edwardsiella ictaluri.

Methods and Results:

An Edwardsiella ictaluri-specific PCR assay was developed utilizing two features of the ribosomal DNA gene clusters. The first feature is the presence of two ribosomal gene clusters located in tandem to one another (the inter-ribosomal spacer, IRS). This characteristic is present in the Edwardsiella

genus but absent in the other sequenced members of the Enterobacteriaceae. The second feature is the presence of an intervening sequence (IVS) in the 23S rRNA gene of Edw. ictaluri. To verify the specificity of this assay, we tested genomic DNA TPX-0005 from a variety of bacterial species. The IVS/IRS PCR assay results in an c. 2000-bp product from all Edw. ictaluri isolates tested, but not from any other species including Edwardsiella tarda.

Conclusions:

The IVS/IRS PCR assay is highly specific for Edw. ictaluri and useful as a tool for identifying this pathogen.

Significance and Impact of the Study:

This research verifies the specificity of PCR-based assay for Edw. Ictaluri, and we describe this assay as a highly

versatile diagnostic tool for its identification.”
“Aspirin, whose active ingredient is sodium salicylate, is the most widely used drug worldwide, but it is not recommended for children because it may cause Reye’s syndrome. High doses old of salicylate also induce temporary hearing loss and tinnitus; while these disorders are believed to disappear when treatment is discontinued some data suggest that prolonged treatment may be neurotoxic. To investigate its ototoxicity, immature, postnatal day 3 rat cochlear organotypic cultures were treated with salicylate. Salicylate did not damage the sensory hair cells, but instead damaged the spiral ganglion neurons (SGN) and their peripheral fibers in a dose-dependent manner. The cross-sectional area of SGN decreased from 205 mu m(2) in controls to 143, 116, and 91 mu m(2) in cultures treated with 1, 3, or 5 mM salicylate, respectively.

Previous studies demonstrate that restraint stress is associated with increased amyloid beta (A beta) and decreased brain-derived neurotrophic factor (BDNF) levels in the brain. A beta deposition, synaptic loss, and neurodegeneration define major hallmarks of AD, and BDNF is responsible for the maintenance of neurons. In contrast to restraint stress, repeated injections of sub-anxiogenic doses of the corticotrophin releasing factor receptor agonist urocortin1 (Ucn1) administered in the basolateral amygdala (BLA) of rats elicits persistent anxiety-like responses. We hypothesized that both restraint stress and Ucn1-induced anxiety would contribute to a neurobiological

abnormality that would change the levels of A beta BAY 11-7082 mouse precursor

protein (APP) and A beta as well as BDNF and pre-synaptic markers. In the first experiment, adult male Wister rats (n=5) were subjected to 3-h restraint, as compared to unstressed controls. In the second experiment, adult male Wistar rats (n=6) were subjected to sub-anxiogenic doses of Ucn1 (6 fmol/100 nl) administered in the BLA for 5 consecutive days, as compared to controls. Following each respective treatment, the social interaction (SI) test was performed to measure anxiety-like behavior. Protein studies were then conducted to quantify levels of APP, A beta, BDNF and presynaptic proteins in the prefrontal cortex (PFC). In both experiments,

we detected differences in either AZD8931 purchase corticosterone levels or the SI test associated with a stress response. Furthermore, our findings indicate that both restraint stress and Ucn1 administration in the BLA lead to increased Cepharanthine APP and A beta deposition. However, restraint-induced stress leads to reductions in the levels of BDNF and presynaptic markers, while Ucn1-induced anxiety is associated with increases in the levels of each respective protein. This demonstrates a convergent role for stress response and Ucn1-induced anxiety in the regulation of APP and A beta, but opposing roles for each respective treatment in the regulation of BDNF and presynaptic markers. (C) 2011 IBRO. Published by Elsevier Ltd. All rights reserved.”
“Previously, we reported that extracellular high-mobility group box 1 (HMGB1) functions as an innate alarmin implicated in cardiac allograft acute rejection. We now present evidence suggesting that HMGB1 is pivotal in inducing interleukin-17 (IL-17)-producing alloreactive T cells by stimulating dendritic cells secretion of IL-6. Those IL-17(+) T cells are likely to be the major effector cells responsible for the early stage of cardiac allograft rejection through mediating an influx of neutrophils into allografts, and therefore, blockade of IL-17A significantly prolonged murine cardiac allograft survival.

In PXE patients, we found similar, although not identical

results for the Gla proteins in the circulation and dermal tissue. However, the VK serum concentration in PXE patients was significantly decreased compared with controls. Our findings allow us to conclude that ectopic mineralization in the PXE-like syndrome EPZ5676 mouse and in PXE results from a deficient protein carboxylation of VK-dependent inhibitors of calcification. Although in PXE-like patients this is due to mutations in the GGCX gene, a deficiency of the carboxylation co-factor VK is at the basis of the decreased activity of calcification inhibitors in PXE. Laboratory Investigation (2010) 90, 895-905; doi:10.1038/labinvest.2010.68; published online 5 April 2010″
“Study aim. – To study the yield of routine EEG in geriatric patients.

Patients and methods. – We examined standard EEG recordings of 701 patients aged 84.6 +/- 6.4 years. These were

performed over a 15 month-period in a geriatric hospital. The majority of patients were hospitalized and 46.5% suffered from multiple medical problems.

Results. – We found EEG abnormalities in 392/701 (56%) patients. These consisted of permanent diffuse slowing, either isolated (17.1%) or with intermixed epileptiform abnormalities (2.4%), focal slowing (15.4%), intermittent diffuse slowing (8.9%), triphasic waves (1.14%), periodic epileptiform discharges (0.57%), flat and inactive tracing (0.14%), status epilepticus (0.99%), seizures (0.42%), interictal learn more epileptiform abnormalities (8.7%). Epileptiform abnormalities (both ictal and interictal) were observed in 92/701 (13.1%) patients. These were

focal in the majority of cases (85.9%), most frequent in temporal regions (42%), followed by centroparietal (20.2%) and temporo-parieto-occipital carrefour regions (17.2%), but less frequent in frontal (6.3%) and occipital regions (3.8%). We found sleep activity without other EEG abnormalities in 13.7% of patients and PIK3C2G subclinical rhythmic electrographic discharge in adult (SREDA) in 1% of cases.

Conclusions. – In this study, EEG abnormalities were very common, which reflects the high frequency of cerebral dysfunction in geriatric patients. These abnormalities are of various types, often suggestive of different aetiologies, and may be helpful in clinical management. (C) 2010 Elsevier Masson SAS. All rights reserved.”
“To maintain normal retinal function, retinal pigment epithelial (RPE) cells engulf photoreceptor outer segments (ROS) enriched in free fatty acids (FFAs). We have previously demonstrated fatty acid-binding protein 5 (FABP5) downregulation in the RPE/choroidal complex in a mouse model of aging and early age-related macular degeneration. FABPs are involved in intracellular transport of FFAs and their targeting to specific metabolic pathways. To elucidate the role of FABP5 in lipid metabolism, the production of the FABP5 protein in a human RPE cell line was inhibited using RNA interference technology.