A new curve fitting based rating prediction algorithm for recommender systems

summary:The most algorithms for Recommender Systems (RSs) are based on a Collaborative Filtering (CF) approach, in particular on the Probabilistic Matrix Factorization (PMF) method. It is known that the PMF method is quite successful for the rating prediction. In this study, we consider the problem of rating prediction in RSs. We propose a new algorithm which is also in the CF framework; however, it is completely different from the PMF-based algorithms. There are studies in the literature that can increase the accuracy of rating prediction by using additional information. However, we seek the answer to the question that if the input data does not contain additional information, how we can increase the accuracy of rating prediction. In the proposed algorithm, we construct a curve (a low-degree polynomial) for each user using the sparse input data and by this curve, we predict the unknown ratings of items. The proposed algorithm is easy to implement. The main advantage of the algorithm is that the running time is polynomial, namely it is $\theta(n^2)$, for sparse matrices. Moreover, in the experiments we get slightly more accurate results compared to the known rating prediction algorithms

Hepatocellular carcinoma in Pakistan: where do we stand?

Context: From the 1970s till the mid 1990s, hepatitis B was the most common etiological factor for hepatocellular carcinoma (HCC) in Pakistan. Afterwards, a shift in HCC etiology was observed with a steady rise in hepatitis C virus (HCV) related HCC cases. HCV-3a, which is the most prevalent genotype, is also most frequent in HCV related HCC. There was an increase in the proportion of non-B non-C (NBNC) HCC cases as well, which might be attributed to an increase in non-alcoholic fatty liver disease. Evidence Acquisition: The age-standardized rate for HCC is 7.64/100 000 in males and 2.8/100 000 in females. Male to female ratio is 3.6:1. Usual age of presentation is in the fifth and sixth decade. Most patients present with advanced disease, as they are not in a regular surveillance program. This is more so for patients with NBNC chronic liver disease. As many sonologists in Pakistan are practicing without sufficient training to pick up early lesions, alpha-fetoprotein is still recommended to compliment ultrasound in the surveillance of HCC. Results: Majority of HCC patients present with nonresectable disease. Interventions such as transarterial chemoembolization, radiofrequency ablation, resection and chemotherapy including sorafenib are available in selected centers. Pakistan appears to be in an area of intermediate endemicity for HCC. There is a need for population based epidemiological studies to estimate the exact disease burden. Conclusions: Measures to prevent the spread of hepatitis C and B can slow down the epidemic rise in the incidence of HCC in the coming decades. There is a need to implement a proper surveillance program to identify HCC cases at an early stage

Integrating depression care within NCD provision in Bangladesh and Pakistan : a qualitative study

Background Co-morbidity of depression with other non-communicable diseases (NCDs) worsens clinical outcomes for both conditions. Low- and middle-income countries need to strengthen mechanisms for detection and management of co-morbid depression within NCDs. The Behavioural Activation for Comorbid Depression in Non-communicable Disease (BEACON) study explored the acceptability and feasibility of integrating a brief depression intervention (behavioural activation, BA) into NCD services in healthcare facilities in Bangladesh and Pakistan. Methods Face-to-face qualitative interviews were conducted with 43 patients and 18 health workers attending or working in NCD centres in four healthcare facilities in Bangladesh and Pakistan, and with three policy makers in each country. The interviews addressed four research questions (1) how NCD care is delivered, (2) how NCD patients experience distress, (3) how depression care is integrated within NCD provision, and (4) the challenges and opportunities for integrating a brief depression intervention into usual NCD care. The data were analysed using framework analysis, organised by capability, opportunity and motivation factors, cross-synthesised across countries and participant groups. Results Patients and health workers described NCD centres as crowded and time pressured, with waiting times as long as five hours, and consultation times as short as five minutes; resulting in some patient frustration. They did not perceive direct links between their distress and their NCD conditions, instead describing worries about family and finance including affordability of NCD services. Health worker and policy maker accounts suggested these NCD centres lacked preparedness for treating depression in the absence of specific guidelines, standard screening tools, recording systems or training. Barriers and drivers to integrating a brief depression intervention reflected capability, opportunity and motivation factors for all participant groups. While generally valuing the purpose, significant challenges included the busy hospital environment, skill deficits and different conceptions of depression. Conclusions Given current resource constraints and priorities, integrating a brief psychological intervention at these NCD centres appears premature. An opportune first step calls for responding to patients’ expressed concerns on service gaps in provisioning steady and affordable NCD care. Acknowledging differences of conceptions of depression and strengthening psychologically informed NCD care will in turn be required before the introduction of a specific psychological intervention such as BA

Pathological intracranial extradural hematoma in a 10-year-old child

A nontraumatic spontaneous extradural hematoma, in a fully conscious 10-year-old male child, caused by a solitary eosinophilic granuloma of calvarium presented as a case of localized painful swelling of the head, which rapidly expanded and decreased in size. A plain CT-scan of the head with bone window revealed eroded right parietal bone with subperiosteal debris and extradural hematoma of mixed density. Immediate evacuation of the extradural clot and complete excision of the lesion was performed to prevent the deterioration of the patient and to achieve the histological diagnosis for further management

Laser Targeted Oligo Ligation (LTOL) to Identify DNA Sequences in the Vicinity of a Single Subnuclear Structure in a Single Cell

Gene loci are organized around nuclear substructures, forming gene hubs which provide a level of transcriptional control. To date, most techniques used to investigate the genes in these hubs have been based on using material from bulk cells. This makes identifying specific gene associations difficult. Here we describe the Laser Targeted Oligo Ligation (LTOL) technique that was developed to identify DNA sequences around a single subnuclear structure on a single-cell basis by targeting these regions with two-photon irradiation