A review on reactivity and stability of heterogeneous metal catalysts for deoxygenation of bio-oil model compounds

Andrew Ng Kay Lup,Faisal Abnisa,Wan Mohd Ashri Wan Daud,Mohamed Kheireddine Aroua 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.56 No.-

Catalytic deoxygenation is a fundamental process for bio-oil upgrading due to its high oxygen contentwhich will result in lower heating value, corrosion and instability issues. The discovery of an excellentheterogeneous deoxygenation metal catalyst with high deoxygenation activity is a necessarybreakthrough for an optimized bio-oil catalytic deoxygenation. For an effective deoxygenation supportedmetal catalyst, properties such as high H2 sticking coefficient, optimal metal-oxygen bond strength andsuitable acid strength from support are needed to ensure facile scission of C O bonds and activation ofH2 and O-containing compounds. Metals such as Fe, Ru, Sn, W, Zr and supports such as C, TiO2, ZrO2 whichare oxophilic were also observed to enhance direct removal of oxygen from O-containing compounds dueto their high C O and C¼O bond affinities. The choice of support is important to ensure it has optimalphysicochemical properties for facile deoxygenation and the optimal acid strength to enhance C Ohydrogenolysis activity while minimizing coke formation. The choice of metal is dependent on the type ofmodel compound since different metals catalyze different reaction pathways of the deoxygenation ofmodel compounds. This review presents on the use of heterogeneous metal catalysts in thedeoxygenation of bio-oil model compounds through several perspectives which are catalytic properties,reaction conditions, deactivation and regeneration of metal catalysts. In addition, several outlooks on thefeasible range of reaction condition for catalytic deoxygenation and criteria of excellent deoxygenationsupported metal catalysts were also expressed in this article based on the studies on the literatures.

Orthogonal filter banks with region Log-TiedRank covariance matrices for face recognition

Ng, Cong Jie,Low, Cheng Yaw,Toh, Kar-Ann,Kim, Jaihie,Teoh, Andrew Beng Jin Elsevier 2018 Journal of visual communication and image represen Vol.55 No.-

<P><B>Abstract</B></P> <P>With the capability of fusing varying features from a specific image region, the Region Covariance Matrices (RCM) image descriptor has been evidenced plausible in face recognition. However, a systematic study for RCM, regarding which features to be fused in particular, remains absent. This paper therefore explores several features derived from the orthogonal filter ensembles, i.e., Identity Transform, Discrete Haar Transform, Discrete Cosine Transform, and Karhunen-Loève Transform, for feature encoding in RCM. Aside from that, we also outline a RCM variant, dubbed Region Log-TiedRank Covariance Matrices (RLTCM) in this paper. The RLTCM descriptor, on average, exhibits dramatic performance gain over RCM as well as state-of-the-art descriptors, especially when probe sets far deviated from the face gallery. Furthermore, we discern that the RLTCM descriptor defined based on Identity Transform, i.e., the simplest form of orthogonal filters, and other learning-free orthogonal filters yield impressive performance on par with the learning-based counterparts.</P>

The Association of Alcohol Use Disorder with Perioperative Complications following Primary Total Hip Arthroplasty

( Andrew R. Horn ),( Keith B. Diamond ),( Mitchell K. Ng ),( Rushabh M. Vakharia ),( Michael A. Mont ),( Orry Erez ) 대한고관절학회 2021 Hip and Pelvis Vol.33 No.4

Purpose: Alcohol use disorder is a leading mental health disorder in the United States. Few studies evaluating the association of alcohol use disorder following primary total hip arthroplasty (THA) have been reported. Therefore, the purpose of this study was to determine whether patients with alcohol use disorder undergoing primary THA have higher rates of: 1) in-hospital lengths of stay (LOS); 2) complications (medical/implant-related); and 3) costs. Materials and Methods: Using a nationwide claims database from January 1st, 2005 to March 31st, 2014, patients with alcohol use disorder undergoing primary THA were identified and matched to a comparison group according to age, sex, and various comorbidities, resulting in 230,467 patients who were included in the study (n=38,416) and a matched-cohort (n=192,051). Outcomes of interest included comparison of LOS, 90-day medical and 2-year implant-related complications, and costs. A P-value less than 0.002 was considered statistically significant. Results: Patients with alcohol use disorder had longer in-hospital LOS (4 days vs 3 days; P<0.0001) as well as higher frequency and odds ratio (OR) of 90-day medical (45.94% vs 12.25%; OR, 2.89; P<0.0001) and 2-year implant-related complications (17.71% vs 8.46%; OR, 1.97; P<0.0001). Patients in the study group incurred higher 90-day costs of care ($17,492.63 vs $14,921.88; P<0.0001). Conclusion: With the growing prevalence of alcohol use disorder in the United States, the current investigation can be utilized to evaluate the need for interventions prior to THA which can potentially minimize the rates of morbidity and mortality within this population.

Banana tissue culture and nutrient enhancement for food security and income generation among people living with AIDS in the Lake Victoria basin

Appolinary Andrew Alex Manyama,Esther Wamono,John H. Muyonga,Grace Wamue – Ngare,Mary Nduta Mwangi,Zipporah W.Ng’ang’a 한국외국어대학교(글로벌캠퍼스) 아프리카연구소 2010 Asian Journal of African Studies Vol.28 No.-

This project undertook a survey in Rachuonyo (Kenya), Bukoba (Tanzania) and Rakai (Uganda) districts to assess the contribution of banana to the household food security and nutrition of PLWHA and assessed the potential nutritional benefit of providing nutrient enhanced banana to PLWHA. Data were collected through interviews with 373 PLWHA and key informants (local agricultural support staff and personnel from PLWHA support agencies) and using focus group discussions. A banana based nutrient enhanced food supplement made by blending banana flour (61%) with soybean flour (39%) and multi‐nutrient fortificant pre‐mix (0.2% of mixture) was distributed to 15 respondents and their nutrient intake estimated. The majority (71.5%) of the survey respondents were females aged 20‐50 years; most had no higher than primary level education and the majority were small scale farmers (with gardens <1 acre). Most of the respondents produced and consumed bananas. The study population was generally food insecure. Banana contributed substantially to household food intake for PLWHA in the 3 districts. Based on the energy and nutrient intake data, PLWHA required supplementary food. The product obtained from banana nutrient enhancement contained 459.7 kcal, 15% protein and substantial levels of vital vitamins and minerals. The product was well accepted and increased energy and nutrient intake by the recipients. At the recorded intake level (average of 66g per person per day), intake of energy and a few nutrients was still below recommended daily allowances (RDA) and about 204 g of the nutrient enhanced banana flour was required to achieve RDA.

Banana tissue culture and nutrient enhancement for food security and income generation among people living with AIDS in the Lake Victoria basin

Appolinary Andrew Alex Manyama,Esther Wamono,John H. Muyonga,Grace Wamue - Ngare,Mary Nduta Mwangi,Zipporah W.Ng’ang’a 한국외국어대학교 아프리카연구소 2010 Asian Journal of African Studies Vol.28 No.-

This project undertook a survey in Rachuonyo (Kenya), Bukoba (Tanzania) and Rakai (Uganda) districts to assess the contribution of banana to the household food security and nutrition of PLWHA and assessed the potential nutritional benefit of providing nutrient enhanced banana to PLWHA. Data were collected through interviews with 373 PLWHA and key informants (local agricultural support staff and personnel from PLWHA support agencies) and using focus group discussions. A banana based nutrient enhanced food supplement made by blending banana flour (61%) with soybean flour (39%) and multi?.nutrient fortificant pre?.mix (0.2% of mixture) was distributed to 15 respondents and their nutrient intake estimated. The majority (71.5%) of the survey respondents were females aged 20-50 years; most had no higher than primary level education and the majority were small scale farmers (with gardens <1 acre). Most of the respondents produced and consumed bananas. The study population was generally food insecure. Banana contributed substantially to household food intake for PLWHA in the 3 districts. Based on the energy and nutrient intake data, PLWHA required supplementary food. The product obtained from banana nutrient enhancement contained 459.7 kcal, 15% protein and substantial levels of vital vitamins and minerals. The product was well accepted and increased energy and nutrient intake by the recipients. At the recorded intake level (average of 66g per person per day), intake of energy and a few nutrients was still below recommended daily allowances (RDA) and about 204 g of the nutrient enhanced banana flour was required to achieve RDA.

Crossed Renal Ectopia and Aorto-Occlusive Disease: A Management Strategy

Eugene Ng,Ian Campbell,Andrew MTL Choong,Nigel Dunglison,Maged Aziz 대한흉부외과학회 2015 Journal of Chest Surgery (J Chest Surg) Vol.48 No.5

We present a rare case of a patient with aortoiliac occlusive disease on the background of type A crossed renal ectopia, for whom open surgical intervention was required. Aortic exposure in patients with concomitant crossed renal ectopia can present technical challenges to the vascular surgeon. The knowledge of variations in the ectopic renal blood supply is of paramount importance when performing surgery to treat this condition and affects the choice of surgical exposure. We present and discuss the operative details of our patient and outline an approach to this subset of patients.

Identifiability and Privacy in Pluripotent Stem Cell Research

Isasi, R.,Andrews, Peter W.,Baltz, Jay M.,Bredenoord, Annelien L.,Burton, P.,Chiu, I.M.,Hull, S.,Jung, J.W.,Kurtz, A.,Lomax, G.,Ludwig, T.,McDonald, M.,Morris, C.,Ng, H.,Rooke, H.,Sharma, A.,Stacey, G Cell Press 2014 Cell stem cell Vol.14 No.4

Data sharing is an essential element of research; however, recent scientific and social developments have challenged conventional methods for protecting privacy. Here we provide guidance for determining data sharing thresholds for human pluripotent stem cell research aimed at a wide range of stakeholders, including research consortia, biorepositories, policy-makers, and funders.

Interfacial modulus mapping of layered dental ceramics using nanoindentation

Theocharopoulos, Antonios L,Bushby, Andrew J,P'ng, Ken MY,Wilson, Rory M,Tanner, K Elizabeth,Cattel, Michael J The Korean Academy of Prosthodonitics 2016 The Journal of Advanced Prosthodontics Vol.8 No.6

PURPOSE. The aim of this study was to test the modulus of elasticity (E) across the interfaces of yttria stabilized zirconia (YTZP) / veneer multilayers using nanoindentation. MATERIALS AND METHODS. YTZP core material (KaVo-Everest, Germany) specimens were either coated with a liner (IPS e.max ZirLiner, Ivoclar-Vivadent) (Type-1) or left as-sintered (Type-2) and subsequently veneered with a pressable glass-ceramic (IPS e.max ZirPress, Ivoclar-Vivadent). A $5{\mu}m$ (nominal tip diameter) spherical indenter was used with a UMIS CSIRO 2000 (ASI, Canberra, Australia) nanoindenter system to test E across the exposed and polished interfaces of both specimen types. The multiple point load - partial unload method was used for E determination. All materials used were characterized using Scanning Electron Microscopy (SEM) and X - ray powder diffraction (XRD). E mappings of the areas tested were produced from the nanoindentation data. RESULTS. A significantly (P<.05) lower E value between Type-1 and Type-2 specimens at a distance of $40{\mu}m$ in the veneer material was associated with the liner. XRD and SEM characterization of the zirconia sample showed a fine grained bulk tetragonal phase. IPS e-max ZirPress and IPS e-max ZirLiner materials were characterized as amorphous. CONCLUSION. The liner between the YTZP core and the heat pressed veneer may act as a weak link in this dental multilayer due to its significantly (P<.05) lower E. The present study has shown nanoindentation using spherical indentation and the multiple point load - partial unload method to be reliable predictors of E and useful evaluation tools for layered dental ceramic interfaces.

Preoperative Serum Albumin Levels Predict Treatment Cost in Total Hip and Knee Arthroplasty

Sarah E. Rudasill,Andrew Ng, BS,Atul F. Kamath 대한정형외과학회 2018 Clinics in Orthopedic Surgery Vol.10 No.4

Background: Hypoalbuminemia (serum albumin < 3.5 g/dL) is associated with increased morbidity and mortality in patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA). However, costs associated with hypoalbuminemia remain unknown. This study investigated the effect of serum albumin on direct treatment costs, length of stay (LOS), and readmissions for primary and revision THA and TKA patients. Methods: All adult patients at a single institution undergoing primary or revision THA or TKA between January 2014 and December 2016 were retrospectively reviewed. Patients were stratified by preoperative serum albumin level. The primary outcome was total direct costs at index hospitalization. Secondary outcomes included LOS and readmission within 30 days. Multivariable regressions were utilized to adjust for demographics and comorbidities. Results: Of 3,785 patients, 114 (3.0%) had hypoalbuminemia. After adjustment, hypoalbuminemia was associated with a 16.2% increase in costs (β = 0.162; 95% confidence interval [CI], 0.112 to 0.213; p < 0.001), representing an average cost increase of $3,383 (95% CI, $2,281 to $4,485) relative to costs for serum albumin > 4.5 g/dL. The increased total costs were significantly higher in revision ($4,322, p = 0.034) than in primary ($3,446, p < 0.001) procedures. In adjusted regression, each 1.0 g/dL increase in serum albumin yielded a 6.6% reduction in costs (β = –0.066; 95% CI, –0.090 to –0.042]; p < 0.001), for average savings of $1,282 (95% CI, $759 to $1,806) per unit albumin. Adjusted regressions demonstrated that a 1-point increase in serum albumin reduced readmissions by 53% (odds ratio, 0.47; 95% CI, 0.31–0.73; p = 0.001) and LOS by 0.6 days (β = –0.60; 95% CI, –0.76 to –0.44; p < 0.001). Conclusions: Hypoalbuminemia is associated with increased total direct costs, LOS, and readmissions following primary and revision THA and TKA. Future efforts to predict and address total costs should take into consideration the patient's preoperative serum albumin levels.

Stand-Alone Cervical Cages in 2-Level Anterior Interbody Fusion in Cervical Spondylotic Myelopathy: Results from a Minimum 2-Year Follow-up

Eugene Pak-Lin Ng,Andrew Siu-Leung Yip,Keith Hay-Man Wan,Michael Siu Hei Tse,Kam Kwong Wong,Tik-Koon Kwok,Wing Cheung Wong 대한척추외과학회 2019 Asian Spine Journal Vol.13 No.2

Study Design: A retrospective review of patients who underwent 2-level anterior cervical discectomy and fusion (ACDF) with stand-alone polyetheretherketone (PEEK) cages for cervical spondylotic myelopathy (CSM). Purpose: To evaluate the efficacy of stand-alone PEEK cage in 2-level cervical interbody fusion for CSM. Overview of Literature: ACDF is a standard surgical procedure to treat degenerative disc disease. However, the use of additional anterior plating for 2-level ACDF remains controversial. Methods: We reviewed outcomes of patients who underwent 2-level ACDF with stand-alone PEEK cages for CSM over a 7-year period (2007–2015) in a regional hospital. Japanese Orthopaedic Association (JOA) score, fusion rate, subsidence rate, cage migration, and cervical alignment by the C2–7 angle as well as the local segmental angle (LSA) of the cervical spine were assessed. Results: In total, 31 patients (mean age, 59 years; range, 36–87 years) underwent 2-level ACDF with a cage-only construct procedure between 2007 and 2015. The minimum follow-up was 24 months; mean follow-up was 51 months. C3–5 fusion was performed in 45%, C4–6 fusion in 32%, and C5–7 fusion in 23%. Mean JOA score improved from 10.1±2.2 to 13.9±2.1 (p<0.01) at the 24-month follow-up. Fusion was achieved in all patients. Subsidence occurred in 22.5% of the cages but was not associated with differences in JOA scores, age, sex, or levels fused. Lordosis of the C2–7 angle and LSA increased after surgery, which were maintained for up to 1 year but subsequently disappeared after 2 years, yet the difference was not statistically significant. No cage migration was noted; two patients developed adjacent segment disease requiring posterior laminoplasty 3 years after ACDF. Conclusions: The use of a stand-alone PEEK cage in a 2-level cervical interbody fusion achieves satisfactory improvements in both clinical outcomes and fusion.