Knee Angle Estimation from Surface EMG during Walking Using Attention-Based Deep Recurrent Neural Networks: Feasibility and Initial Demonstration in Cerebral Palsy.

Accurately estimating knee joint angle during walking from surface electromyography (sEMG) signals can enable more natural control of wearable robotics like exoskeletons. However, challenges exist due to variability across individuals and sessions. This study evaluates an attention-based deep recurrent neural network combining gated recurrent units (GRUs) and an attention mechanism (AM) for knee angle estimation. Three experiments were conducted. First, the GRU-AM model was tested on four healthy adolescents, demonstrating improved estimation compared to GRU alone. A sensitivity analysis revealed that the key contributing muscles were the knee flexor and extensors, highlighting the ability of the AM to focus on the most salient inputs. Second, transfer learning was shown by pretraining the model on an open source dataset before additional training and testing on the four adolescents. Third, the model was progressively adapted over three sessions for one child with cerebral palsy (CP). The GRU-AM model demonstrated robust knee angle estimation across participants with healthy participants (mean RMSE 7 degrees) and participants with CP (RMSE 37 degrees). Further, estimation accuracy improved by 14 degrees on average across successive sessions of walking in the child with CP. These results demonstrate the feasibility of using attention-based deep networks for joint angle estimation in adolescents and clinical populations and support their further development for deployment in wearable robotics.

Case 302: Supratentorial Lymphocytic Inflammation with Parenchymal Perivascular Enhancement Responsive to Steroids.

HISTORY: Part one of this case appeared 4 months previously and may contain larger images. A 21-year-old immunocompetent man who was a long-term resident of Qatar presented to the emergency department with recurrent episodes of unprovoked generalized tonic-clonic seizures lasting 2-3 minutes that spontaneously resolved and were associated with postictal confusion. The patient also had progressive mild diplopia, intermittent dizziness, and numbness in the left arm over the course of 3 months. The patient did not have any other systemic symptoms or chronic medical diseases. He did not have any history of intake of illicit drugs, supplements, or regular medications; he had not received any recent vaccinations; and he had not undergone any surgical procedures. He had no history of travel. At presentation, vital signs were normal. Neurologic examination showed mild left homonymous hemianopia, normal gait with no cerebellar signs, and preserved sensations, power, tone, and reflexes in all four limbs. An electroencephalogram showed no epileptiform discharges. Chest CT and extensive laboratory work-up, including viral, fungal, bacterial, and parasite work-up, thyroid function tests, and immunologic blood tests yielded normal results. Those included normal complete and differential blood counts and normal serum chemistry. Serum analysis was negative for antinuclear antibody, Sjögren syndrome antigens A and B, cytoplasmic antineutrophil cvtoplasmic antibody, and paraneoplastic profile. Serum evaluation was also negative for human immunodeficiency virus type 1 and type 2 RNA, and Brucella, Schistosoma, and toxoplasma antibodies. Venereal Disease Research Laboratory (VDRL) and rapid plasma regain (RPR) test results were negative. Cerebrospinal fluid (CSF) analysis revealed clear fluid and normal pressure and biochemistry, except for elevated protein concentration (0.48 g/L) (normal range, 0.15-0.45 g/L). There were 43 leukocytes/µL (99% lymphocytes) (normal range, 0-5 leukocytes/µL; lymphocytes range, 40%-80%), with no atypical or malignant cells. CSF Gram staining, acid-fast staining, cryptococcal antigen, varicella-zoster virus polymerase chain reaction (PCR), herpes simplex virus PCR, VDRL, and RPR test results were negative. CSF cultures did not show any evidence of growth of bacteria, fungi, or acid-fast bacillus. CSF flow cytometry did not show a monoclonal lymphoid population. No CSF oligoclonal bands were detected. Conventional brain MRI with intravenous administration of contrast material and perfusion study were performed and included different sequences (Figs 1-3).

Case 302.

History A 21-year-old immunocompetent man who was a long-term resident of Qatar presented to the emergency department with recurrent episodes of unprovoked generalized tonic-clonic seizures lasting 2-3 minutes that spontaneously resolved and were associated with postictal confusion. The patient also had progressive mild diplopia, intermittent dizziness, and numbness in the left arm over the course of 3 months. The patient did not have any other systemic symptoms or chronic medical diseases. He did not have any history of intake of illicit drugs, supplements, or regular medications; he had not received any recent vaccinations; and he had not undergone any surgical procedures. He had no history of travel. At presentation, vital signs were normal. Neurologic examination showed mild left homonymous hemianopia, normal gait with no cerebellar signs, and preserved sensations, power, tone, and reflexes in all four limbs. An electroencephalogram showed no epileptiform discharges. Chest CT and extensive laboratory work-up, including viral, fungal, bacterial, and parasite work-up, thyroid function tests, and immunologic blood tests yielded normal results. Those included normal complete and differential blood counts and normal serum chemistry. Serum analysis was negative for antinuclear antibody, Sjögren syndrome antigens A and B, cytoplasmic antineutrophil cvtoplasmic antibody, and paraneoplastic profile. Serum evaluation was also negative for human immunodeficiency virus type 1 and type 2 RNA, and Brucella, Schistosoma, and toxoplasma antibodies. Venereal Disease Research Laboratory (VDRL) and rapid plasma regain (RPR) test results were negative. Cerebrospinal fluid (CSF) analysis revealed clear fluid and normal pressure and biochemistry, except for elevated protein concentration (0.48 g/L) (normal range, 0.15-0.45 g/L). There were 43 leukocytes/µL (99% lymphocytes) (normal range, 0-5 leukocytes/µL; lymphocytes range, 40%-80%), with no atypical or malignant cells. CSF Gram staining, acid-fast staining, cryptococcal antigen, varicella-zoster virus polymerase chain reaction (PCR), herpes simplex virus PCR, VDRL, and RPR test results were negative. CSF cultures did not show any evidence of growth of bacteria, fungi, or acid-fast bacillus. CSF flow cytometry did not show a monoclonal lymphoid population. No CSF oligoclonal bands were detected. Conventional brain MRI with intravenous administration of contrast material and a perfusion study were performed and included different sequences (Figs 1-3).

Mini-open Anterior Pelvic Osteotomy and Spica Casting for Primary Closure of the Pelvis in Infants With Classic Bladder Exstrophy.

BACKGROUND: The objective of this study was to investigate the efficacy and safety of mini-open Salter-like anterior pelvic osteotomy followed by spica casting as an adjunct to urological reconstruction in infants with classic bladder exstrophy (CBE). METHODS: Twenty-eight infants with CBE were operated upon according to the following protocol: initial bilateral mini-open Salter-like osteotomies followed by urological reconstruction and subsequent spica casting for 3 to 4 weeks. Postoperative clinical and radiologic assessments of wound complications and union were done, respectively. During subsequent follow-ups, the foot progression angle (FPA), the interpubic (IP) distance, interischial (IS) distance, and the IS/IP ratio were measured. The Pearson correlation was used to correlate between age at the time of last follow-up, the FPA, the IP and IS distances, and the IS/IP ratio. RESULTS: The mean age at the time of operation was 5.89±0.89 months. The operative procedure took 10 to 15 minutes (mean of 12.5±1.5 min) for each side and the blood loss was negligible. Tension-free complete approximation of the symphysis was achieved in all cases. No wound complications were reported in any case. The total duration of the cast was 3.07±0.14 weeks. The mean duration of follow-up was 4.78±3.09 years. Strong positive correlation was found between the IP and IS distances ( r =0.833, P <0.0001) as well as the IS distance and age (r=0.455, P =0.015). CONCLUSION: Mini-open anterior pelvic osteotomy and spica casting may provide a minimally invasive and effective option for closure of the pelvis in infants with CBE. LEVEL OF EVIDENCE: Level IV-case series.

The role of contemporary digital tools and technologies in COVID-19 crisis: An exploratory analysis.

Following the COVID-19 pandemic, there has been an increase in interest in using digital resources to contain pandemics. To avoid, detect, monitor, regulate, track, and manage diseases, predict outbreaks and conduct data analysis and decision-making processes, a variety of digital technologies are used, ranging from artificial intelligence (AI)-powered machine learning (ML) or deep learning (DL) focused applications to blockchain technology and big data analytics enabled by cloud computing and the internet of things (IoT). In this paper, we look at how emerging technologies such as the IoT and sensors, AI, ML, DL, blockchain, augmented reality, virtual reality, cloud computing, big data, robots and drones, intelligent mobile apps, and 5G are advancing health care and paving the way to combat the COVID-19 pandemic. The aim of this research is to look at possible technologies, processes, and tools for addressing COVID-19 issues such as pre-screening, early detection, monitoring infected/quarantined individuals, forecasting future infection rates, and more. We also look at the research possibilities that have arisen as a result of the use of emerging technology to handle the COVID-19 crisis.

Assessment of Conventional Solvent Extraction vs. Supercritical Fluid Extraction of Khella (Ammi visnaga L.) Furanochromones and Their Cytotoxicity.

BACKGROUND: Khella (Ammi visnaga Lam.) fruits (Apiaceae) are rich in furanochromones, mainly khellin and visnagin, and are thus incorporated in several pharmaceutical products used mainly for treatment of renal stones. METHODS: The objective of this study was to compare the yield of khellin and visnagin obtained using different conventional solvents and supercritical fluid extraction (SCFE) with carbon dioxide (containing 5% methanol as co-solvent). Water, acetone and ethanol (30% and 95%) were selected as conventional solvents. RESULTS: Highest extract yield was obtained from 30% ethanol (15.44%), while SCFE gave the lowest yield (4.50%). However, the percentage of furanochromones were highest in SCFE (30.1%), and lowest in boiling water extract (5.95%). HPLC analysis of conventional solvent extracts showed other coumarins that did not appear in supercritical fluid extraction chromatogram due to non-selectivity of solvent extraction. Ammi visnaga extracts as well as standard khellin and visnagin were tested for their cytotoxic activity using sulforhodamine B assay on breast cancer (MCF-7) and hepatocellular carcinoma (Hep G2) cell lines. Results revealed a strong cytotoxic activity (IC50 < 20 µg/mL) for the SCFE and standard compounds (khellin and visnagin) (IC50 ranging between 12.54 ± 0.57 and 17.53 ± 1.03 µg/mL). However, ethanol and acetone extracts had moderate cytotoxic activity (IC50 20-90 µg/mL) and aqueous extract had a weak activity (IC50 > 90 µg/mL). CONCLUSIONS: Thus, supercritical fluid extraction is an efficient, relatively safe, and cheap technique that yielded a more selective purified extract with better cytotoxic activity.

Can Ethanolic Leaf Extract of Olive or Black Mulberry Substitute Sodium Hypochlorite as a Root Canal Irrigant? An In Vitro Study.

AIM: This study aimed to evaluate Olea europaea (olive) leaves and Morus nigra (black mulberry) leaves as potential natural alternatives to sodium hypochlorite (NaOCl) endodontic irrigant. Their antimicrobial activity against Enterococcus faecalis (E. faecalis) and their effects on both root dentin microhardness and push-out bond strength of resin sealer/root dentin were assessed. METHODOLOGY: Fifty-four extracted teeth were selected. Samples were grouped according to the irrigant used: group I (control): 2.5% NaOCl, group II: 8% ethanolic extract of Olea europaea, and group III: 2% ethanolic extract of Morus nigra. Antibacterial activity (n = 6) was evaluated after each canal was autoclaved, inoculated with E. faecalis, and incubated. Canals were sampled before and after chemicomechanical canal preparation with 2 mL of irrigant. The colony-forming units (CFUs) were counted at 1/10 and 1/100 broth concentrations. Vickers hardness number (VHN) of root dentin (n = 6) was measured before and after root canal preparation and irrigation. Push-out bond strength testing (n = 9) was carried out following preparation, irrigation, obturation, and thermocycling. Results were considered statistically significant at p ≤0.05. RESULTS: Following irrigation, the CFUs of E. faecalis were significantly reduced with no significant difference in the CFU count between all groups at both broth concentrations. A significant reduction in root dentin microhardness resulted in all groups following irrigation, with Morus nigra resulting in the lowest percentage reduction (26.42 ± 1.12). The lowest significant mean push-out bond strength was revealed in the Olea europaea group (3.372 ± 1.513 MPa). CONCLUSION: The use of 2% mulberry (Morus nigra) leaf extract and 8% olive (Olea europaea) leaf extract as alternatives to NaOCl provides promising antimicrobial action against E. faecalis. CLINICAL SIGNIFICANCE: 2% Morus nigra extract may represent a promising natural endodontic irrigant.

Proapoptotic Activity of Achillea membranacea Essential Oil and Its Major Constituent 1,8-Cineole against A2780 Ovarian Cancer Cells.

Among the hundreds of reported Achillea species, A. membranacea (Labill.) DC. is one of the six that grow in Jordan. Many species of this genus are used in folk medicine to treat a variety of ailments and several biological and pharmacological activities have been ascribed to their essential oil (EO). For this study, the EO obtained from a specimen of A. membranacea grown in Jordan was analyzed by GC-MS. Ninety-six compounds were detected, of which oxygenated monoterpenes was the predominant class (47.9%), followed by non-terpene derivatives (27.9%), while sesquiterpenes represented 14.2% of the total composition. The most abundant compound in the EO was 1,8-cineole (21.7%). The cytotoxic activity of the EO was evaluated against three cancer cell lines (MCF7, A2780 and HT29), and one normal fibroblast cell line (MRC5) by MTT assay. Significant growth inhibition was observed in EO-exposed A2780 and HT29 cells (IC50 = 12.99 and 14.02 µg/mL, respectively), while MCF7 and MRC5 were less susceptible. The EO induced apoptosis and increased the preG1 events in A2780 cells. 1,8-Cineole, the major constituent of the EO, exhibited submicromolar cytotoxicity against A2780 cells, and was 42 times more selective against MRC5 cells. Its cytotoxicity against A2780 cells was comparable with that of doxorubicin, but 1,8-cineole was more selective for MRC5 normal cells. Interestingly, 1,8-cineole enhanced apoptosis in A2780, and caused a remarkable dose-dependent increase in preG1 events. Thus, 1,8-cineole has demonstrated promising cytotoxic and proapoptotic properties.

Genome-wide association study of psoriasis in an Egyptian population.

Psoriasis is a chronic inflammatory disorder of the skin, with genetic factors reportedly involved in the disease pathogenesis. Numerous studies reported psoriasis candidate genes. However, these tend to involve mostly in the European and Asian populations. Here, we report the first genome-wide association study (GWAS) in an Egyptian population, identifying susceptibility variants for psoriasis using a two-stage case-control design. In the first discovery stage, we carried out a genome-wide association analysis using the Infinium® Global Screening Array-24 v1.0, on 253 cases and 449 control samples of Egyptian descent. In the second replication stage, 26 single-nucleotide polymorphisms (SNPs) were selected for replication in additional 321 cases and 253 controls. In concordance with the findings from previous studies on other populations, we found a genome-wide significant association between the MHC locus and the disease at rs12199223 (Pcomb  = 6.57 × 10-18 ) and rs1265181 (Pcomb  = 1.03 × 10-10 ). Additionally, we identified a novel significant association with the disease at locus, 4q32.1 (rs12650590, Pcomb  = 4.49 × 10-08 ) in the vicinity of gene GUCY1A3, and multiple suggestive associations, for example rs10832027 (Pcomb  = 7.28 × 10-06 ) and rs3770019 (Pcomb  = 1.02 × 10-05 ). This proposes the existence of important interethnic genetic differences in psoriasis susceptibility. Further studies are necessary to elucidate the downstream pathways of the new candidate loci.

Assessment of combined fractional CO2 and tranexamic acid in melasma treatment.

BACKGROUND: Melasma continues to be a disease that is difficult to treat with no fully satisfactory results. The role of a fractional CO2 laser in its treatment is controversial. The addition of tranexamic acid (TXA) might be helpful. OBJECTIVES: To assess the efficacy of a low-power fractional CO2 laser alone versus its combination with tranexamic acid used either topically or intradermally for melasma treatment. METHODS: A randomized comparative split-face study included a total of thirty female patients with bilateral, symmetrical melasma. The whole face was subjected to treatment via a low-power (12 Watts) fractional ablative CO2 laser. One side was randomly assigned to topical application of tranexamic acid solution after the session immediately or intradermal microinjection of tranexamic acid prior to the laser session. Sessions were conducted every 4-6 weeks for five consecutive sessions. Assessments were done using the melasma area severity index MASI score, melanin index (MI), and erythema index (EI) before sessions and 2 weeks after the final session. RESULTS: After treatment, there was significant reduction in the MASI score on both sides of the face; the side treated with the fractional CO2 laser alone and the side treated with fractional CO2 laser combined with TXA (topically or intradermal injection) (P-values 0.007, <0.001, and 0.016, respectively). MI was significantly lower on the side receiving fractional CO2 laser alone and the side receiving fractional CO2 laser combined with intradermal injection of TXA (P-values <0.001 and 0.003, respectively), while the EI showed significant improvement only on the side receiving fractional CO2 laser alone (P-value = 0.023). Although patients reported no differences in improvement on either treated side, the degree of improvement regarding the MASI score was better on the side receiving fractional CO2 laser alone. Regarding MI, the degree of improvement was higher on the side receiving fractional CO2 laser combined with intradermal injection of TXA than on the side receiving fractional CO2 laser alone; however, this improvement did not reach statistical significance. Minimal complications occurred in the form of mild pain. CONCLUSION: A low-power fractional CO2 laser is an effective, safe treatment for melasma. However, the addition of tranexamic acid (either topically or intradermally) to a fractional CO2 laser should be further studied. Lasers Surg. Med. 51:27-33, 2019. © 2018 Wiley Periodicals, Inc.

Courtyard geometry's effect on energy consumption of AlKharga city residential buildings, Egypt.

The research aim is to clarify the effect of courtyard placement, the ratio between length and width, and courtyard orientation on energy consumption in residential buildings in hot and dry climates, to seek planning and designing alternatives for new cities and new residential complexes that are consistent with the environment and climate and save the consumption of energy used in the buildings. The research method was conducted through Design Builder software for simulation purposes. The reference model with the 157.25 m2 which accommodates a central square courtyard measuring 5 m × 5 m, on a residential building model in the New Valley Governorate of Kharga City, Egypt. The courtyard simulation is aimed to determine Less energy consumption inside the different case studies, in 9 courtyard placements The studied alternatives for Courtyard Placement, are (the center of the building, sub facades, and main facades). The different ratios are (1:1, 1.25:1, 1.5:1-1.75:1, 2:1, 2.25:1, 2.5-1). The longitudinal axis of the Courtyard has been oriented to the east-west direction for all placements, and north-south direction for all placements. Also, (orientation angle is Zero), it offered the percentages of better and worst cases in each position of the courtyard. The research findings suggest that the best Placement of the Courtyard that achieved the highest rate of saving of energy consumed inside the used building model was at the southwestern façade, with a saving rate of 18.73%. Then, the Placement of the Courtyard at the northwestern and southeastern facades with a saving rate of 17.91%, with a length-to-width ratio (2.5:1) if the longitudinal axis of the Courtyard is oriented in the north-south direction, Through the study, we conclude that the placement and orientation of the courtyard and its regular formation have contributed to rationalizing energy consumption in residential buildings, the study reached some important standards that could represent a methodological framework for designing contemporary residential buildings with an energy-efficient inner courtyard.

Attention-Based Deep Recurrent Neural Network to Estimate Knee Angle During Walking from Lower-Limb EMG.

Accurate prediction of joint angle during walking from surface electromyography (sEMG) offers the potential to infer movement intention and therefore represents a potentially useful approach for adaptive control of wearable robotics. Here, we present the use of a recurrent neural network (RNN) with gated recurrent units (GRUs) and an attention mechanism to estimate knee angle during overground walking from sEMG and its initial offline validation in healthy adolescents. Our results show that the attention mechanism improved estimation accuracy by focusing on the most relevant parts of the input dataset within each time window, particularly muscles active during knee excursion. Sensitivity analysis revealed knee extensor and flexor muscles to be most salient in accurately estimating joint angle. Additionally, we demonstrate the ability of the GRU-RNN approach to accurately estimate knee angle during overground walking in a child with cerebral palsy (CP) in the presence of exoskeleton knee extension assistance. Collectively, our findings establish the initial feasibility of using this approach to estimate user movement from sEMG, which is particularly important for developing robotic exoskeletons for children with neuromuscular disorders such as CP.

Tissue levels of suppressor of cytokine signaling-3 (SOCS-3) in mycosis fungoides.

Mycosis fungoides (MF) is a type of cutaneous T-cell lymphoma with proposed multifactorial etiology. Suppressor of cytokine signaling-3 (SOCS-3) is one of the proteins expressed in MF. Its exact role in disease pathogenesis has not yet been thoroughly investigated. This study aimed to assess the expression of SOCS-3 in patients' skin with mycosis fungoides to elucidate their possible role in the pathogenesis in MF. 30 patients with mycosis fungoides and 30 age and sex-matched healthy controls were included. After clinical examination, tissue levels of SOCS-3 were measured by ELISA. The level of expression of SOCS-3 was significantly upregulated in the lesional tissue compared to perilesional SOCS-3 level in patients' group (P < 0.001), and both levels were higher than the SOCS-3 level in control group (P < 0.001). In addition, there was a statistically significant positive correlation between lesional SOCS-3 level and itching in patients' group (P < 0.001). Regarding lesional and perilesional SOCS-3 levels in each stage, there was a significant increase in lesional SOCS-3 levels in comparison to perilesional level whether in stage Ia, Ib, and IIa; (P < 0.001), (P < 0.001) and (P < 0.001), respectively. Increased tissue levels of SOCS-3 patients with mycosis fungoides point to a role that SOCS-3 could play in its pathogenesis. Also, high levels of SOCS-3 in MF patients with itching suggest a role in the pathogenesis of this symptom. These findings may prove helpful in formulating a new treatment modality in addition to the current treatment of MF.

Claustrum sparing sign in seronegative limbic encephalitis.

Background: Limbic encephalitis (LE) is a rare variant of autoimmune encephalitis. It often manifests with subacute neuropsychiatric symptoms of agitation, delusions, variable seizure semiology, and short-term memory loss. Seronegative limbic encephalitis can pose a diagnostic conundrum owing to its inadequately understood pathophysiology. Case presentation: We report a rare case of a young male with subacute neuropsychiatric manifestations of delusions, agitations and seizures. He was diagnosed with seronegative limbic encephalitis (SNLE). Brain MRI demonstrated bilateral Claustrum sparing sign. An EEG showed continuous left-sided epileptiform discharges in periodic to predominantly left middle temporal. Patient condition gradually improved with pulsed methylprednisolone, intravenous immunoglobulins and anti-seizure medications. Conclusion: Claustrum remains one of the least understood neuroanatomical structures. Claustrum sign has been reported in febrile infection-related epilepsy syndrome (FIRES), LE, and autoimmune refractory epilepsy. To the best of our knowledge, we report the first case in literature with Claustrum sparing sign in seronegative Limbic Encephalitis. Further experimental models and researches are warranted to better understand the unique function of the claustrum and unravel possible other attributable auto-antibodies, which could alter treatment and prognosis.

Susceptibility-weighted Imaging in Neuroradiology: Practical Imaging Principles, Pearls and Pitfalls.

Susceptibility-weighted imaging (SWI) was one of the recent and helpful advancement in magnetic resonance imaging. Its utilization -provided valuable information for the radiologists in multiple fields, including neuroradiology. SWI was able to demonstrate cerebral paramagnetic and diamagnetic substances. Therefore, the applications of this imaging technique were diverse in research and clinical neuroradiology. This article reviewed the basic technical steps, various clinical applications of SWI, and potential limitations. The practicing radiologist needs to be oriented about using SWI and phase images in the right- and left-handed MRI systems to demonstrate different brain pathologies, including neurovascular diseases, traumatic brain injuries, brain tumors, infectious and inflammatory, and neurodegenerative diseases.

FROST: Fallback Voice Apps Recommendation for Unhandled Voice Commands in Intelligent Personal Assistants.

Intelligent personal assistants (IPAs) such as Amazon Alexa, Google Assistant and Apple Siri extend their built-in capabilities by supporting voice apps developed by third-party developers. Sometimes the smart assistant is not able to successfully respond to user voice commands (aka utterances). There are many reasons including automatic speech recognition (ASR) error, natural language understanding (NLU) error, routing utterances to an irrelevant voice app, or simply that the user is asking for a capability that is not supported yet. The failure to handle a voice command leads to customer frustration. In this article, we introduce a fallback skill recommendation system (FROST) to suggest a voice app to a customer for an unhandled voice command. There are several practical issues when developing a skill recommender system for IPAs, i.e., partial observation, hard and noisy utterances. To solve the partial observation problem, we propose collaborative data relabeling (CDR) method. To mitigate hard and noisy utterance issues, we propose a rephrase-based relabeling technique. We evaluate the proposed system in both offline and online settings. The offline evaluation results show that the FROST system outperforms the baseline rule-based system. The online A/B testing results show a significant gain of customer experience metrics.

Two-Stage Voice Application Recommender System for Unhandled Utterances in Intelligent Personal Assistant.

Intelligent personal assistants (IPA) enable voice applications that facilitate people's daily tasks. However, due to the complexity and ambiguity of voice requests, some requests may not be handled properly by the standard natural language understanding (NLU) component. In such cases, a simple reply like "Sorry, I don't know" hurts the user's experience and limits the functionality of IPA. In this paper, we propose a two-stage shortlister-reranker recommender system to match third-party voice applications (skills) to unhandled utterances. In this approach, a skill shortlister is proposed to retrieve candidate skills from the skill catalog by calculating both lexical and semantic similarity between skills and user requests. We also illustrate how to build a new system by using observed data collected from a baseline rule-based system, and how the exposure biases can generate discrepancy between offline and human metrics. Lastly, we present two relabeling methods that can handle the incomplete ground truth, and mitigate exposure bias. We demonstrate the effectiveness of our proposed system through extensive offline experiments. Furthermore, we present online A/B testing results that show a significant boost on user experience satisfaction.

Optic cupping secondary to periventricular leukomalacia: A potential mimic for normal pressure glaucoma.

We herein present a case of periventricular leukomalacia (PVL) with secondary optic pathway denervation atrophy, which was initially labeled as normal tension glaucoma. However, given the discordant clinical and ophthalmologic findings, brain magnetic resonance imaging was requested which proved PVL to be the underlying process to the patient's decreased visual acuity. In addition to presenting the ophthalmologic findings, we are emphasizing the pivotal role of neuroimaging in ruling out central causes of optic atrophy/hypoplasia and making this clinical distinction by demonstrating optic pathway atrophy associated with PVL.

Essential Oil Biodiversity of Achillea ligustica All. Obtained from Mainland and Island Populations.

BACKGROUND: The genus Achillea is rich in essential oil (EO) with high chemical diversity. In this study, eight EO samples obtained from flowers and leaves of Achillea ligustica All. collected on the Mediterranean mainland and island locations were analyzed to evaluate their possible chemical diversity. METHODS: Sixteen samples of EO were analyzed by GC-MS, leading to the identification of 95 compounds in the leaves and 86 compounds in the flowers; a statistical analysis was performed to determine the chemical polymorphism. RESULTS: Monoterpenes, such as ß-pinene, borneol, ɑ-terpineol and isobornyl acetate, were more abundant in the continental samples, while the insular samples were richer in 1,8-cineole. Fragranyl acetate and fragranol were detected in remarkable concentrations in sample 8. The fruits of sample 8 were then cultivated under controlled agronomic conditions, providing plants rich in these compounds (sample 9). The geographical variability influenced the EO compositions, with unique observed chemotypes and a high degree of diversity among samples collected in various areas (mainland or island). Statistical analyses did not reveal any pattern between the geographical provenience and the compositions. CONCLUSION: Samples were distributed based on the plant organ, confirming the already reported high degree of chemical polymorphism of this species. Sample 8 could be used as a source of fragranol and fragranyl acetate, with potential applications in the insecticidal and pheromone industries.

Antioxidant and cytotoxic activity of polyphenolic compounds isolated from the leaves of Leucenia leucocephala.

CONTEXT: Cancer is a serious clinical problem to the health care system. Anticancer drugs have been extracted from plants containing phenolic compounds. Leucenia species (Fabaceae) contain a variety of bioactive components of numerous biological and pharmacological properties. OBJECTIVE: This study explored the constitutive polyphenols of Leucenia leucocephala Lam. growing in Egypt and evaluated the antioxidant and cytotoxic activity. MATERIALS AND METHODS: Chemical structures of the isolated compounds from the leaves of L. leucocephala were established by spectral techniques (UV, (1)H, and (13)C NMR, MS). RESULTS: Chromatographic separation of 80% MeOH extract of the leaves of L. leucocephala have resulted in a novel flavonoid-galloyl glycoside [myricetin 3-O-(2',3'4'-tri-O-galloyl)-α-L-rhamnopyranoside] with three known polyphenolic compounds isolated for the first time from this species (apigenin 7-O-ß-D-glucuronopyranoside methyl ester, luteolin 7-O-ß-D-glucuronopyranoside methyl ester, and 1,3,6-tri-O-galloyl-ß-D-glucopyranose) and seven known previously isolated compounds. Also, 80% methanol extract exhibited high antioxidant activity (SC(50) = 3.94 µg/ml), which is correlated with its phenolic content. The extract also showed cytotoxic activity against Hep G2 (IC(50) value 1.41 µg/ml) confirming its anticancer activity against hepatocellular carcinoma. Among the tested compounds (4-8) for antioxidant property, compound 7 was the most active compound (SC(50) = 2.49 µg/ml). Also compounds 7 and 8 exhibited high cytotoxic activity (IC(50) = 2.41 and 2.81 µg/ml, respectively). DISCUSSION AND CONCLUSION: These findings demonstrate that the leaves of L. leucocephala contain a considerable amount of polyphenolic compounds with high antioxidant properties, thus it has great potential as a source for natural health products.