380 research outputs found

    Zero-Shot Generalizable End-to-End Task-Oriented Dialog System using Context Summarization and Domain Schema

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    Task-oriented dialog systems empower users to accomplish their goals by facilitating intuitive and expressive natural language interactions. State-of-the-art approaches in task-oriented dialog systems formulate the problem as a conditional sequence generation task and fine-tune pre-trained causal language models in the supervised setting. This requires labeled training data for each new domain or task, and acquiring such data is prohibitively laborious and expensive, thus making it a bottleneck for scaling systems to a wide range of domains. To overcome this challenge, we introduce a novel Zero-Shot generalizable end-to-end Task-oriented Dialog system, ZS-ToD, that leverages domain schemas to allow for robust generalization to unseen domains and exploits effective summarization of the dialog history. We employ GPT-2 as a backbone model and introduce a two-step training process where the goal of the first step is to learn the general structure of the dialog data and the second step optimizes the response generation as well as intermediate outputs, such as dialog state and system actions. As opposed to state-of-the-art systems that are trained to fulfill certain intents in the given domains and memorize task-specific conversational patterns, ZS-ToD learns generic task-completion skills by comprehending domain semantics via domain schemas and generalizing to unseen domains seamlessly. We conduct an extensive experimental evaluation on SGD and SGD-X datasets that span up to 20 unique domains and ZS-ToD outperforms state-of-the-art systems on key metrics, with an improvement of +17% on joint goal accuracy and +5 on inform. Additionally, we present a detailed ablation study to demonstrate the effectiveness of the proposed components and training mechanis

    Personalizing Task-oriented Dialog Systems via Zero-shot Generalizable Reward Function

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    Task-oriented dialog systems enable users to accomplish tasks using natural language. State-of-the-art systems respond to users in the same way regardless of their personalities, although personalizing dialogues can lead to higher levels of adoption and better user experiences. Building personalized dialog systems is an important, yet challenging endeavor and only a handful of works took on the challenge. Most existing works rely on supervised learning approaches and require laborious and expensive labeled training data for each user profile. Additionally, collecting and labeling data for each user profile is virtually impossible. In this work, we propose a novel framework, P-ToD, to personalize task-oriented dialog systems capable of adapting to a wide range of user profiles in an unsupervised fashion using a zero-shot generalizable reward function. P-ToD uses a pre-trained GPT-2 as a backbone model and works in three phases. Phase one performs task-specific training. Phase two kicks off unsupervised personalization by leveraging the proximal policy optimization algorithm that performs policy gradients guided by the zero-shot generalizable reward function. Our novel reward function can quantify the quality of the generated responses even for unseen profiles. The optional final phase fine-tunes the personalized model using a few labeled training examples. We conduct extensive experimental analysis using the personalized bAbI dialogue benchmark for five tasks and up to 180 diverse user profiles. The experimental results demonstrate that P-ToD, even when it had access to zero labeled examples, outperforms state-of-the-art supervised personalization models and achieves competitive performance on BLEU and ROUGE metrics when compared to a strong fully-supervised GPT-2 baselineComment: 11 pages, 4 tables, 31st ACM International Conference on Information and Knowledge Management (CIKM'22

    Synthesis and Characterization of Novel Quadri-dentate Demi-macrocyclic Ligand Having N2O2 as its Donors

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    Abstract: A novel quadric-dentate demi-macrocycle of the type [C14H30N2O2] (ClO4)2¯ was synthesized by 1:2 condensation reaction at high dilution process. The desired demi-macrocycle was characterized by spectral methods such as UV-visible, IR, 1HNMR and elemental analysis. The results obtained were in close conformity with properties and proposed structure

    Ab-initio study of the bandgap engineering of Al(1-x)Ga(x)N for optoelectronic applications

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    A theoretical study of Al(1-x)Ga(x)N, based on full-potential linearized augmented plane wave method, is used to investigate the variations in the bandgap, optical properties and non-linear behavior of the compound with the variation of Ga concentration. It is found that the bandgap decreases with the increase of Ga in Al(1-x)Ga(x)N. A maximum value of 5.5 eV is determined for the bandgap of pure AlN which reaches to minimum value of 3.0 eV when Al is completely replaced by Ga. The static index of refraction and dielectric constant decreases with the increase in bandgap of the material, assigning a high index of refraction to pure GaN when compared to pure AlN. The refractive index drops below 1 for photon energies larger than 14 eV results group velocity of the incident radiation higher than the vacuum velocity of light. This astonishing result shows that at higher energies the optical properties of the material shifts from linear to non-linear. Furthermore, frequency dependent reflectivity and absorption coefficients show that peak value of the absorption coefficient and reflectivity shifts towards lower energy in the UV spectrum with the increase in Ga concentration. This comprehensive theoretical study of the optoelectronic properties of the alloys is presented for the first time which predicts that the material can be effectively used in the optical devices working in the visible and UV spectrum.Comment: 18 pages, 7 figure

    Woodlot farming by smallholder farmers in Ganderbal district of Kashmir, India

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    Forest degradation and deforestation are serious threats to resource conservation, subsistence livelihoods and rural income diversification. Woodlot farming on farms has been established as a potential option to increase forest resources from agricultural landscapes and remove human pressure from forests. The study investigated the land-use and landholding pattern, woodlots types and species preference and extent of spatial distribution, land allocation and growing stock of woodlots in the Ganderbal district of Kashmir. Multistage random sampling technique was employed to select 349 farm woodlots from 12 sample villages. Secondary sources were used to collect village-level data on land-use and landholding pattern. Primary data concerning the trees were collected through farm woodlot inventories. The data were analyzed using simple descriptive statistics. Results revealed that the total land area in the sample villages is 888.60 ha; 521.60 ha (58.70%) is cultivated land, which is mostly (80.78%) occupied by 1244 marginal farmers. The prevalent woodlots established were plantations of Populus, Salix, Robinia or mixed species. The farm woodlots (61.59 ha) contributed 11.81% of cultivated land and 6.93% of the total geographical area. The average growing stocks of woodlots were estimated to be 204.05 m3/ha for Populus, 191.77 m3/ha for Salix, 109.51 m3/ha for Robinia and 62.31 m3/ha for Mixed. The findings suggested that woodlot farming is the key alternative for forest resource production, livelihood resilience and socioeconomic improvement; hence, the policy must be implicated towards the promotion of woodlot farming by re-orienting the land use through farmer’s motivation and technical, financial and farming input assistance

    Beta Blockade Prevents Cardiac Morphological and Molecular Remodelling in Experimental Uremia

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    Heart failure and chronic kidney disease (CKD) share several mediators of cardiac pathological remodelling. Akin to heart failure, this remodelling sets in motion a vicious cycle of progressive pathological hypertrophy and myocardial dysfunction in CKD. Several decades of heart failure research have shown that beta blockade is a powerful tool in preventing cardiac remodelling and breaking this vicious cycle. This phenomenon remains hitherto untested in CKD. Therefore, we set out to test the hypothesis that beta blockade prevents cardiac pathological remodelling in experimental uremia. Wistar rats had subtotal nephrectomy or sham surgery and were followed up for 10 weeks. The animals were randomly allocated to the beta blocker metoprolol (10 mg/kg/day) or vehicle. In vivo and in vitro cardiac assessments were performed. Cardiac tissue was extracted, and protein expression was quantified using immunoblotting. Histological analyses were performed to quantify myocardial fibrosis. Beta blockade attenuated cardiac pathological remodelling in nephrectomised animals. The echocardiographic left ventricular mass and the heart weight to tibial length ratio were significantly lower in nephrectomised animals treated with metoprolol. Furthermore, beta blockade attenuated myocardial fibrosis associated with subtotal nephrectomy. In addition, the Ca++- calmodulin-dependent kinase II (CAMKII) pathway was shown to be activated in uremia and attenuated by beta blockade, offering a potential mechanism of action. In conclusion, beta blockade attenuated hypertrophic signalling pathways and ameliorated cardiac pathological remodelling in experimental uremia. The study provides a strong scientific rationale for repurposing beta blockers, a tried and tested treatment in heart failure, for the benefit of patients with CKD


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    ABSTRACT In present research study, three experiments were launched during January 2011 to December 2011. Experiment I, Epidemiology: A total 1200 faecal samples (100 per month) were collected from farmers Bibrik-sheep (either sexes, 1-5 years old) and analyzed for nematodes prevalence. Experiment II, Sero-diagnosis: The sera samples of healthy and nematodes infected sheep were analyzed through ELISA. Experiment III, Therapeutic trial: comparative efficacy of herbal and synthetic anthelmintics was determined. Results showed that overall 40.25% Bibrik-sheep were infected with nematodes. Five nematode genera were recorded with higher prevalence of Haemonchus (10.42%) followed by Strongyloides (8.75%), Trichostrongylus (7.33%), Nematodirus (6.92%), and Trichuris (6.83%). The older age ewes presented higher nematodes prevalence. These five genera of nematodes were prevalent throughout the year. However, two peaks of nematodes prevalence i.e. March/May and August/December 2011 were observed. The level of nematodes infection was mostly low (< 2000 EPG) and did not impair the sheep productivity seriously. Haemonchus and Trichuris positive samples, based on coprological examination indicated 100% positive sensitivity for each genus of nematode by the ELISA, based on crude somatic antigen, while based on excretory antigen, showed lower (92%) sensitivity. The higher (86-100%) reduction of EPG was recorded in sheep treated with Ivermectin, while lower (68-96%) with Atreefal deedan

    Bi-allelic JAM2 Variants Lead to Early-Onset Recessive Primary Familial Brain Calcification.

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    Primary familial brain calcification (PFBC) is a rare neurodegenerative disorder characterized by a combination of neurological, psychiatric, and cognitive decline associated with calcium deposition on brain imaging. To date, mutations in five genes have been linked to PFBC. However, more than 50% of individuals affected by PFBC have no molecular diagnosis. We report four unrelated families presenting with initial learning difficulties and seizures and later psychiatric symptoms, cerebellar ataxia, extrapyramidal signs, and extensive calcifications on brain imaging. Through a combination of homozygosity mapping and exome sequencing, we mapped this phenotype to chromosome 21q21.3 and identified bi-allelic variants in JAM2. JAM2 encodes for the junctional-adhesion-molecule-2, a key tight-junction protein in blood-brain-barrier permeability. We show that JAM2 variants lead to reduction of JAM2 mRNA expression and absence of JAM2 protein in patient's fibroblasts, consistent with a loss-of-function mechanism. We show that the human phenotype is replicated in the jam2 complete knockout mouse (jam2 KO). Furthermore, neuropathology of jam2 KO mouse showed prominent vacuolation in the cerebral cortex, thalamus, and cerebellum and particularly widespread vacuolation in the midbrain with reactive astrogliosis and neuronal density reduction. The regions of the human brain affected on neuroimaging are similar to the affected brain areas in the myorg PFBC null mouse. Along with JAM3 and OCLN, JAM2 is the third tight-junction gene in which bi-allelic variants are associated with brain calcification, suggesting that defective cell-to-cell adhesion and dysfunction of the movement of solutes through the paracellular spaces in the neurovascular unit is a key mechanism in CNS calcification

    Formal Reasoning on Natural Language Descriptions of Processes

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    The existence of unstructured information that describes processes represents a challenge in organizations, mainly because this data cannot be directly referred into process-aware ecosystems due to ambiguities. Still, this information is important, since it encompasses aspects of a process that are left out when formalizing it on a particular modelling notation. This paper picks up this challenge and faces the problem of ambiguities by acknowledging its existence and mitigating it. Specifically, we propose a framework to partially automate the elicitation of a formal representation of a textual process description, via text annotation techniques on top of natural language processing. The result is the ATDP language, whose syntax and semantics are described in this paper. ATDP allows to explicitly cope with several interpretations of the same textual description of a process model. Moreover, we link the ATDP language to a formal reasoning engine and show several use cases. A prototype tool enabling the complete methodology has been implemented, and several examples using the tool are provided.Peer ReviewedPostprint (author's final draft
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