Miracle-dz/UniFAR-FTUs huggingface dataset:
Efficient retrieval of recommendations in a matrix factorization framework

Low-rank Matrix Factorization (MF) methods provide one of the simplest and most effective approaches to collaborative filtering. This paper is the first to investigate the problem of efficient retrieval of recommendations in a MF framework. We reduce the retrieval in a MF model to an apparently simple task of finding the maximum dot-product for the user vector over the set of item vectors. However, to the best of our knowledge the problem of efficiently finding the maximum dot-product in the general case has never been studied. To this end, we propose two techniques for efficient search -- (i) We index the item vectors in a binary spatial-partitioning metric tree and use a simple branch and-bound algorithm with a novel bounding scheme to efficiently obtain exact solutions. (ii) We use spherical clustering to index the users on the basis of their preferences and pre-compute recommendations only for the representative user of each cluster to obtain extremely efficient approximate solutions. We obtain a theoretical error bound which determines the quality of any approximate result and use it to control the approximation. Both these simple techniques are fairly independent of each other and hence are easily combined to further improve recommendation retrieval efficiency. We evaluate our algorithms on real-world collaborative-filtering datasets, demonstrating more than ×7 speedup (with respect to the naive linear search) for the exact solution and over ×250 speedup for approximate solutions by combining both techniques.
Performance Still Matters

What explains low levels of trust in government institutions in democratizing Latin American countries? The authors examine this question in the Dominican Republic, employing data from three surveys conducted over 1994 to 2001. Their analysis finds that trust in government institutions is shaped primarily by perceptions of economic and political performance by government. There is little evidence of a relationship between civic engagement and institutional trust, and no relationship between democratic values and institutional trust. They find a curvilinear effect between socioeconomic status and institutional trust, with middle-sector groups significantly less trusting of government institutions than either the poor or the wealthy. Age has a nonlinear effect as older generations, who experienced authoritarianism as children, are considerably more trusting of democratic institutions, contradicting predictions by culturalist early-life socialization arguments. The authors conclude that low trust per se is not the major challenge for governance.
Vascular Patterns and Perfusion of Mucogingival Tissues and their Relation to Periodontal Flap Design

Abstract : This investigation sought to describe the three dimensional microvascular anatomy of the periodontium utilizing silicone Microfil and acrylic perfusion techniques. A second aim of this study was to evaluate vascular response to surgical injury utilizing fluorescein angiography and laser doppler velocimetry. A total of seven Rhesus monkeys were used in this study. Four Rhesus monkeys were sacrificed followed by carotid artery cannulation, exsanguination, rinsing, and vascular perfusion of the head utilizing either Batson's 17 corrosion casting medium or silicone Microfil. Batson's perfused specimens (2) were then prepared for scanning electron microscopy and the Microfil specimens (2) were subjected to both hematoxylin and eosin and cleared section analysis. In order to evaluate vascular response to surgical injury, three monkeys were studied with fluorescein angiography and laser doppler velocimetry following three different periodontal flap designs (narrow pedicle, wide pedicle, and envelope flap). Recordings were made at three time intervals (pre-surgery, post flap reflection and replacement, and following flap suturing), and at three tatooed tissue locations (coronal flap margin, base of flap, and midway between the previous two measurements). The findings in this study suggest that the location of vertical incisions at the junction of thick and thin tissues (i.e., at tooth line angles) is associated with the best post surgical perfusion. Tissue thickness appears to be just as important to flap survival as the width to length ratio of flaps. Thesis.
Using a Mobile App to Manage Type 1 Diabetes: The Case of TreC Diabetes

Type 1 diabetes is chronic condition due to the autoimmune destruction of the insulin-producing beta cells in the pancreas. We present TreC Diabetes, a system consisting of a mobile diary and a web dashboard allowing patients to record disease-related information, which can be visualized by diabetologists through a dedicated dashboard. We also present the results of an observational study to assess the user acceptance of the system.
The Role of Anthracyclines in Combination Chemotherapy for the Treatment of Follicular Lymphoma: Retrospective Study of the Intergruppo Italiano Linfomi on 761 Cases

In order to elucidate the role of anthracycline based combination chemotherapy regimens for the treatment of follicular lymphoma we conducted a retrospective study on a large series of patients with a histologically confirmed diagnosis of follicular lymphoma. The Italian lymphoma intergroup (ILI) promoted a retrospective study of patients with follicular lymphoma treated in cooperative trials between 1985 and 1996. Six hundred and thirty three cases were treated with an anthracycline-containing regimen and 128 patients were treated without anthracyclines. The two groups were prognostically comparable; in particular, no difference was observed according to both IPI and ILI prognostic index. Results showed a complete remission (CR) rate for patients treated with anthracyclines was 69.2% and overall response rate was 92.5%. After a median follow-up of 51 months (54 months for patients still alive), the 5- and 10-year overall survival (OS) rates were 80 and 66%, respectively. Disease-free survival (DFS) and failure-free survival (FFS) rates at 5 years were 61 and 49%, respectively. In the group of patients treated with combination chemotherapy not including anthracyclines, the CR rate was 67.5% and the overall response rate was 85.4%. A longer OS (80% at 5 years) was observed in patients treated with anthracyclines compared to 67% OS rate in patients treated without anthracyclines <formula>(<italic>p</italic>=0.0004). </formula> FFS was significantly longer in patients treated with anthracyclines (49 vs. 34% <formula><italic>p</italic>=0.006</formula>). Patients treated with anthracyclines with low or intermediate risk according to ILI prognostic index showed a significantly longer OS (<formula><italic>p</italic>=0.0001</formula> and <formula><italic>p</italic>=0.0009,</formula> respectively); those in the high-risk group showed a trend for a longer survival. In conclusion, this retrospective study shows that patients with follicular lymphoma treated with an anthracycline containing regimen had a better outcome compared to patients treated with other combination regimens non including anthracyclines in terms of CRs, OS and FFS. On the basis of these results anthracycline-containing regimens (ACR) should be considered as the standard treatment of patients with advanced follicular lymphoma.
Inhibition of Histone Deacetylation Blocks Cardiac Hypertrophy Induced by Angiotensin II Infusion and Aortic Banding

Background— A number of distinct stress signaling pathways in myocardium cause cardiac hypertrophy and heart failure. Class II histone deacetylases (HDACs) antagonize several stress-induced pathways and hypertrophy. However, cardiac hypertrophy induced by transgenic overexpression of the homeodomain only protein, HOP, can be prevented by the nonspecific HDAC inhibitors trichostatin A and valproic acid, suggesting that alternate targets that oppose class II HDAC function might exist in myocardium. We tested the effects of several HDAC inhibitors, including a class I HDAC-selective inhibitor, SK-7041, on cardiac hypertrophy induced by angiotensin II (Ang II) treatment or aortic banding (AB). Methods and Results— Cardiac hypertrophy was induced by chronic infusion of Ang II or by AB in mice or rats and evaluated by determining the ratio of heart weight to body weight or to tibia length, cross-sectional area, or echocardiogram. Cardiac hypertrophy induced by Ang II or AB for 2 weeks was significantly reduced by simultaneous administration of trichostatin A, valproic acid, or SK-7041. Echocardiogram revealed that exaggerated left ventricular systolic dimensions were relieved by HDAC inhibitors. HDAC inhibitors partially reversed preestablished cardiac hypertrophy and improved survival of AB mice. The expressions of atrial natriuretic factor, &agr;-tubulin, &bgr;-myosin heavy chain, and interstitial fibrosis were reduced by HDAC inhibition. Conclusions— These results suggest that the predominant effect of HDAC inhibition, mainly mediated by class I HDACs, is to prevent cardiac hypertrophy in response to a broad range of agonist and stretch stimuli.
Vibrotactile stimulus frequency optimization for the haptic BCI prototype

The paper presents results from a psychophysical study conducted to optimize vibrotactile stimuli delivered to subject finger tips in order to evoke the somatosensory responses to be utilized next in a haptic brain computer interface (hBCI) paradigm. We also present the preliminary EEG evoked responses for the chosen stimulating frequency. The obtained results confirm our hypothesis that the hBCI paradigm concept is valid and it will allow for rapid stimuli presentation in order to improve information-transfer-rate (ITR) of the BCI.
The Thin Latissimus Dorsi Perforator‐Based Free Flap for Resurfacing

The authors present their experience with “thin” latissimus dorsi perforator‐based free flaps for resurfacing defects. Perforator‐based free flaps have been used for various kinds of reconstruction by preserving important donor structures. The thin latissimus dorsi perforatorbased free flap included only the skin and superficial adipose layer to reduce its bulkiness by dissection through the superficial fascial plane. This flap was used in 12 clinical cases, without flap necrosis or other serious postoperative complications. All of the patients were examined by preoperative power Doppler ultrasound in the spectral Doppler mode to search for the most reliable perforator. This noninvasive ultrasound technique determines the exact location and course of and ensures the reliable flow of the perforators; therefore, it greatly assists microsurgeons in saving operation time and in selecting the most suitable design for perforator flap reconstruction. We used perforators that were identified several centimeters from the lateral border of the latissimus dorsi muscle. The thin flap dimensions could be safely designed for flaps measuring up to 20 cm in length and 8 cm in width for primary closure of the donor site. Generally, a long pedicle is not required for resurfacing reconstructions, where small recipient arteries in the bed are acceptable for anastomosis with pedicles. However, pedicle dissection to the proximal vessels through the latissimus dorsi muscle was required when it was necessary to match the recipient vein for anastomosis. The authors conclude that this thin latissimus dorsi perforator‐based free flap has great potential for resurfacing because of its constant thickness, easy elevation with the help of power Doppler ultrasound information, and proper flap size for moderate defects caused by scar contracture release, superficial tumor ablation, and so on. (Plast. Reconstr. Surg. 107: 374, 2001.)
Role of Membrane Microdomains in Compartmentation of cAMP Signaling

Spatially restricting cAMP production to discrete subcellular locations permits selective regulation of specific functional responses. But exactly where and how cAMP signaling is confined is not fully understood. Different receptors and adenylyl cyclase isoforms responsible for cAMP production are not uniformly distributed between lipid raft and non-lipid raft domains of the plasma membrane. We sought to determine the role that these membrane domains play in organizing cAMP responses in HEK293 cells. The freely diffusible FRET-based biosensor Epac2-camps was used to measure global cAMP responses, while versions of the probe targeted to lipid raft (Epac2-MyrPalm) and non-raft (Epac2-CAAX) domains were used to monitor local cAMP production near the plasma membrane. Disruption of lipid rafts by cholesterol depletion selectively altered cAMP responses produced by raft-associated receptors. The results indicate that receptors associated with lipid raft as well as non-lipid raft domains can contribute to global cAMP responses. In addition, basal cAMP activity was found to be significantly higher in non-raft domains. This was supported by the fact that pharmacologic inhibition of adenylyl cyclase activity reduced basal cAMP activity detected by Epac2-CAAX but not Epac2-MyrPalm or Epac2-camps. Responses detected by Epac2-CAAX were also more sensitive to direct stimulation of adenylyl cyclase activity, but less sensitive to inhibition of phosphodiesterase activity. Quantitative modeling was used to demonstrate that differences in adenylyl cyclase and phosphodiesterase activities are necessary but not sufficient to explain compartmentation of cAMP associated with different microdomains of the plasma membrane.
On the Asymptotic Throughput of OFDMA Systems with Best-M CQI Feedback

In order to enable channel-aware scheduling, orthogonal frequency-division multiple access (OFDMA) systems require each user to feed back channel quality information (CQI) relative to each frequency resource block (RB) toward the base station. 3GPP LTE systems relieve the overhead entailed by CQI feedback by employing the "best-M" feedback scheme prescribing each user to report the index of the M best RB's along with one single CQI measure. In order to provide a flexible tool for system design, we derive an upper bound for the downlink throughput with best-M CQI feedback for both single and multi-antenna communication schemes. Asymptotic analysis shows that, for a large number of users, multiuser diversity provides an SNR gain that scales as 1/M.
Time-delayed feedback in neurosystems

The influence of time delay in systems of two coupled excitable neurons is studied in the framework of the FitzHugh–Nagumo model. A time delay can occur in the coupling between neurons or in a self-feedback loop. The stochastic synchronization of instantaneously coupled neurons under the influence of white noise can be deliberately controlled by local time-delayed feedback. By appropriate choice of the delay time, synchronization can be either enhanced or suppressed. In delay-coupled neurons, antiphase oscillations can be induced for sufficiently large delay and coupling strength. The additional application of time-delayed self-feedback leads to complex scenarios of synchronized in-phase or antiphase oscillations, bursting patterns or amplitude death.
Effect of roscovitine, a cdk1 inhibitor, and of the presence of oocyte on bovine cumulus cell expansion and cyclooxygenase‐2 expression

Oocyte maturation is accompanied by differentiation of surrounding cumulus cells. These cells produce hyaluronic acid (HA) and its storage in intercellular spaces results in expansion of the cells. The cumulus cells also accumulate cyclooxygenase‐2 (cox‐2) during maturation. Both expansion and cox‐2 storage are regulated by FSH and EGF. The aim of this study was to determine whether oocyte meiotic resumption is involved in the regulation of cumulus differentiation or not. We investigated the effects of roscovitine, a reversible inhibitor of meiosis resumption of cattle oocytes on EGF induced expansion and cox‐2 expression at the transcript and protein levels respectively (RT‐PCR and Western blot), in cumulus oocyte complexes (COCs) and cumulus complexes alone (CCs). EGF induced expansion and cox‐2 expression in both COCs and CCs. These effects were prevented by roscovitine, whether in the presence or in the absence of oocyte. However, the oocyte was essential for the reversibility of inhibition by roscovitine. In conclusion, our results indicate that i) oocyte secreted‐factors are not essential for cumulus expansion, and ii) roscovitine mediated inhibition of meiotic resumption also respects the functionality of the surrounding somatic cells. Mol. Reprod. Dev. 65: 114–121, 2003. © 2003 Wiley‐Liss, Inc.
Mitochondrial Calcium and Reactive Oxygen Species Regulate Agonist-Initiated Platelet Phosphatidylserine Exposure

Objective—To study the interactions of cytoplasmic calcium elevation, mitochondrial permeability transition pore (mPTP) formation, and reactive oxygen species formation in the regulation of phosphatidylserine (PS) exposure in platelets. Methods and Results—mPTP formation, but not the degree of cytoplasmic calcium elevation, was associated with PS exposure in wild-type, cyclophilin D–null, ionomycin-treated, and reactive oxygen species–treated platelets. In the absence of the mPTP regulator cyclophilin D, agonist-initiated mPTP formation and high-level PS exposure were markedly blunted, but cytoplasmic calcium transients were unchanged. Mitochondrial calcium (Ca2+mit) transients and reactive oxygen species, key regulators of mPTP formation, were examined in strongly stimulated platelets. Increased reactive oxygen species production occurred in strongly stimulated platelets and was dependent on extracellular calcium entry, but not the presence of cyclophilin D. Ca2+mit increased significantly in strongly stimulated platelets. Abrogation of Ca2+mit entry, either by inhibition of the Ca2+mit uniporter or mitochondrial depolarization, prevented mPTP formation and exposure but not platelet aggregation or granule release. Conclusion—Sustained cytoplasmic calcium levels are necessary, but not sufficient, for high-level PS exposure in response to agonists. Increased Ca2+mit levels are a key signal initiating mPTP formation and PS exposure. Blockade of Ca2+mit entry allows the specific inhibition of platelet procoagulant activity.
Towards Increasing Reliability of Heuristic Evaluation

To date comparative studies have not convinced the HCI community about the reliability of results from usability evaluations. User testing of the same products by different usability teams found different problems (Molich et al., 1999). Discount methods also have the same problem. With heuristic evaluation method, for example, overlaps between evaluators’ results are often as low as 10% (Molich & Robin, 2003). However, the strength of the heuristic evaluation method is in its cost-effectiveness. In a comparative study (Cuomo & Bowen, 1994) of heuristic evaluation, cognitive walkthrough, and interface guidelines, heuristic evaluation found the highest percentage of true problems per hour of inspection (9.3% as compared to 6.8% by cognitive walkthrough and 2.3% by guidelines). Furthermore, there is a pressing need for a discount evaluation method like heuristic evaluation. As a ‘quick and easy to perform’ method, heuristic evaluation was rated as the most commonly used evaluation method by 134 HCI practitioners at CHI 98, CHI 99, and UPA 99 Conferences (Rosenbaum et al., 2000). However, to best benefit from the method, we need to find ways to improve the reliability of its results.
The relative worst order ratio for online algorithms

We define a new measure for the quality of online algorithms, the relative worst order ratio, using ideas from the max/max ratio [Ben-David and Borodin 1994] and from the random order ratio [Kenyon 1996]. The new ratio is used to compare online algorithms directly by taking the ratio of their performances on their respective worst permutations of a worst-case sequence. Two variants of the bin packing problem are considered: the classical bin packing problem, where the goal is to fit all items in as few bins as possible, and the dual bin packing problem, which is the problem of maximizing the number of items packed in a fixed number of bins. Several known algorithms are compared using this new measure, and a new, simple variant of first-fit is proposed for dual bin packing. Many of our results are consistent with those previously obtained with the competitive ratio or the competitive ratio on accommodating sequences, but new separations and easier proofs are found.
Collective entity resolution in relational data

Many databases contain uncertain and imprecise references to real-world entities. The absence of identifiers for the underlying entities often results in a database which contains multiple references to the same entity. This can lead not only to data redundancy, but also inaccuracies in query processing and knowledge extraction. These problems can be alleviated through the use of entity resolution. Entity resolution involves discovering the underlying entities and mapping each database reference to these entities. Traditionally, entities are resolved using pairwise similarity over the attributes of references. However, there is often additional relational information in the data. Specifically, references to different entities may cooccur. In these cases, collective entity resolution, in which entities for cooccurring references are determined jointly rather than independently, can improve entity resolution accuracy. We propose a novel relational clustering algorithm that uses both attribute and relational information for determining the underlying domain entities, and we give an efficient implementation. We investigate the impact that different relational similarity measures have on entity resolution quality. We evaluate our collective entity resolution algorithm on multiple real-world databases. We show that it improves entity resolution performance over both attribute-based baselines and over algorithms that consider relational information but do not resolve entities collectively. In addition, we perform detailed experiments on synthetically generated data to identify data characteristics that favor collective relational resolution over purely attribute-based algorithms.
Stabilization of Mdm2 via Decreased Ubiquitination Is Mediated by Protein Kinase B/Akt-dependent Phosphorylation*

The tumor suppressor p53 is commonly inhibited under conditions in which the phosphatidylinositide 3′-OH kinase/protein kinase B (PKB)Akt pathway is activated. Intracellular levels of p53 are controlled by the E3 ubiquitin ligase Mdm2. Here we show that PKB inhibits Mdm2 self-ubiquitination via phosphorylation of Mdm2 on Ser166 and Ser188. Stimulation of human embryonic kidney 293 cells with insulin-like growth factor-1 increased Mdm2 phosphorylation on Ser166 and Ser188 in a phosphatidylinositide 3′-OH kinase-dependent manner, and the treatment of both human embryonic kidney 293 and COS-1 cells with phosphatidylinositide 3′-OH kinase inhibitor LY-294002 led to proteasome-mediated Mdm2 degradation. Introduction of a constitutively active form of PKB together with Mdm2 into cells induced phosphorylation of Mdm2 at Ser166 and Ser188 and stabilized Mdm2 protein. Moreover, mouse embryonic fibroblasts lacking PKBα displayed reduced Mdm2 protein levels with a concomitant increase of p53 and p21Cip1, resulting in strongly elevated apoptosis after UV irradiation. In addition, activation of PKB correlated with Mdm2 phosphorylation and stability in a variety of human tumor cells. These findings suggest that PKB plays a critical role in controlling of the Mdm2·p53 signaling pathway by regulating Mdm2 stability.