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1.
Int J Surg ; 2024 May 03.
Article in English | MEDLINE | ID: mdl-38701514

ABSTRACT

BACKGROUND: Ageing population is a worldwide phenomenon with correspondingly higher proportion of older patients being treated in the hospital setting. Sarcopenia, which increases with age, has serious negative implications on health, hospitalization and overall postoperative recovery. There is no mutual consensus on perioperative management of sarcopenia in surgical patients in Singapore. The purpose of this study is to create greater clarity pertaining to the recognition of sarcopenia, the application of assessment criteria of sarcopenia and perioperative management of surgical patients in Singapore. METHODS: A modified Delphi consensus consisting of a panel of experts from Singapore forming a multidisciplinary team, including surgeons, geriatricians, anesthesiologists, physiotherapists and dieticians. Eight recommendations were proposed by the steering committee. Literature search from MEDLINE, Embase and Scopus for articles up till June 2023 were performed to support recommendation statements. The expert panel voted on agreement to recommendation statements and graded the level of evidence supporting each statement through surveys to achieve consensus, set at 85% a priori. RESULTS: The panelists underwent two rounds of anonymized, independent voting before reaching consensus for all eight statements. After the first round, seven statements reached consensus, including the corresponding grading for level of evidence. The statement which did not achieve consensus was revised with supporting literature and after the second round of survey, all eight statements and level of evidence reached consensus, completing the Delphi process. These eight statements covered themes to (1) encourage the identification of sarcopenia, (2) guide pre-operative and (3) post-operative management of sarcopenia. CONCLUSION: With the varying approaches in perioperative management, poor understanding of and identification of sarcopenia can result in suboptimal management of sarcopenia in surgical patients. Given the abundance of evidence linking beneficial impact on recovery and post-operative complications with prudent management of sarcopenia, it is imperative and urgent to achieve awareness and consensus.

2.
World J Gastrointest Surg ; 15(11): 2596-2618, 2023 Nov 27.
Article in English | MEDLINE | ID: mdl-38111761

ABSTRACT

BACKGROUND: Branched chain amino acid (BCAA) supplementation has been associated with favourable outcomes in liver malignancies requiring definitive resection or liver transplantation. Currently, there are no updated systematic reviews evaluating the efficacy of perioperative BCAA supplementation in patients undergoing surgery for liver cancer. AIM: To evaluate the efficacy of perioperative BCAA supplementation in patients undergoing surgery for liver cancer. METHODS: A systematic review of randomized control trials and observational studies was conducted on PubMed, Embase, Cochrane Library, Scopus, and Web of Science to evaluate the effect of perioperative BCAA supplementation compared to standard in-hospital diet, in liver cancer patients undergoing surgery. Clinical outcomes were extracted, and a meta-analysis was performed on relevant outcomes. RESULTS: 16 studies including 1389 patients were included. Perioperative BCAA administration was associated with reduced postoperative infection [risk ratio (RR) = 0.58 95% confidence intervals (CI): 0.39 to 0.84, P = 0.005] and ascites [RR = 0.57 (95%CI: 0.38 to 0.85), P = 0.005]. There was also a reduction in length of hospital stay (LOS) [weighted mean difference (WMD) = -3.03 d (95%CI: -5.49 to -0.57), P = 0.02] and increase in body weight [WMD = 1.98 kg (95%CI: 0.35 to 3.61, P = 0.02]. No significant differences were found in mortality, cancer recurrence and overall survival. No significant safety concerns were identified. CONCLUSION: Perioperative BCAA administration is efficacious in reducing postoperative infection, ascites, LOS, and increases body weight in liver cancer patients undergoing surgical resection.

3.
Nutrients ; 15(21)2023 Oct 24.
Article in English | MEDLINE | ID: mdl-37960145

ABSTRACT

The nutritional status of hospitalised patients is often at risk or compromised and predisposed to further deterioration after discharge, leading to poor clinical outcomes, high healthcare costs, and poor quality of life. This paper aims to provide evidence-based best-practice recommendations to address this, supported by a national survey of healthcare professionals in Singapore and reviewed by a multidisciplinary expert panel under the Sarcopenia Interest Group of Society of Parenteral and Enteral Nutrition Singapore (SingSPEN). We advocate screening all patients with a validated tool which includes a disease activity/burden component, an easily accessible dietitian referral pathway for patients at risk of malnutrition, and an individualised nutrition care plan formulated and delivered using a multidisciplinary team approach for patients at risk or with malnutrition. A comprehensive team would include not only dietitians but also physicians, nurses, physiotherapists, speech therapists, and medical social workers working together towards a common goal. Information on why nutrition is important for good health and how it can be achieved should also be provided to all patients and their caregivers before and after hospital discharge. With the above recommendations, we seek to improve upon the current nutrition care processes at discharge for healthcare institutions in Singapore.


Subject(s)
Malnutrition , Patient Discharge , Humans , Singapore , Quality of Life , Malnutrition/diagnosis , Malnutrition/prevention & control , Enteral Nutrition , Hospitals
5.
Nat Commun ; 13(1): 7218, 2022 Nov 24.
Article in English | MEDLINE | ID: mdl-36433968

ABSTRACT

Topological boundary states are well localized eigenstates at the boundary between two different bulk topologies. As long as bulk topology is preserved, the topological boundary mode will endure. Here, we report topological nonlinear parametric amplification of light in a dimerized coupled waveguide system based on the Su-Schrieffer-Heeger model with a domain wall. The good linear transmission properties of the topological waveguide arising from the strong localization of light to the topological boundary is demonstrated through successful high-speed transmission of 30 Gb/s non-return-to-zero and 56 Gb/s pulse amplitude 4-level data. The strong localization of a co-propagating pump and probe to the boundary waveguide is harnessed for efficient, low power optical parametric amplification and wavelength conversion. A nonlinear tuning mechanism is shown to induce chiral symmetry breaking in the topological waveguide, demonstrating a pathway in which Kerr nonlinearities may be applied to tune the topological boundary mode and control the transition to bulk states.

6.
ACS Sens ; 7(8): 2345-2357, 2022 Aug 26.
Article in English | MEDLINE | ID: mdl-35943904

ABSTRACT

NDIR CO2 gas sensors using a 10-cm-long gas channel and CMOS-compatible 12% doped ScAlN pyroelectric detector have previously demonstrated detection limits down to 25 ppm and fast response time of ∼2 s. Here, we increase the doping concentration of Sc to 20% in our ScAlN-based pyroelectric detector and miniaturize the gas channel by ∼65× volume with length reduction from 10 to 4 cm and diameter reduction from 5 to 1 mm. The CMOS-compatible 20% ScAlN-based pyroelectric detectors are fabricated over 8-in. wafers, allowing cost reduction leveraging on semiconductor manufacturing. Cross-sectional TEM images show the presence of abnormally oriented grains in the 20% ScAlN sensing layer in the pyroelectric detector stack. Optically, the absorption spectrum of the pyroelectric detector stack across the mid-infrared wavelength region shows ∼50% absorption at the CO2 absorption wavelength of 4.26 µm. The pyroelectric coefficient of these 20% ScAlN with abnormally oriented grains shows, in general, a higher value compared to that for 12% ScAlN. While keeping the temperature variation constant at 2 °C, we note that the pyroelectric coefficient seems to increase with background temperature. CO2 gas responses are measured for 20% ScAlN-based pyroelectric detectors in both 10-cm-long and 4-cm-long gas channels, respectively. The results show that for the miniaturized CO2 gas sensor, we are able to measure the gas response from 5000 ppm down to 100 ppm of CO2 gas concentration with CO2 gas response time of ∼5 s, sufficient for practical applications as the average outdoor CO2 level is ∼400 ppm. The selectivity of this miniaturized CO2 gas sensor is also tested by mixing CO2 with nitrogen and 49% sulfur hexafluoride, respectively. The results show high selectivity to CO2 with nitrogen and 49% sulfur hexafluoride each causing a minimum ∼0.39% and ∼0.36% signal voltage change, respectively. These results bring promise to compact and miniature low cost CO2 gas sensors based on pyroelectric detectors, which could possibly be integrated with consumer electronics for real-time air quality monitoring.

7.
Sci Rep ; 12(1): 12697, 2022 Jul 26.
Article in English | MEDLINE | ID: mdl-35882882

ABSTRACT

Chemical vapor deposition-based growth techniques allow flexible design of complementary metal-oxide semiconductor (CMOS) compatible materials. Here, we report the deuterated silicon-rich nitride films grown using plasma-enhanced chemical vapor deposition. The linear and nonlinear properties of the films are characterized, and we experimentally confirm that the silicon-rich nitride films grown with SiD4 eliminates Si-H and N-H related absorption. The performance of identical waveguides for films grown with SiH4 and SiD4 are compared demonstrating a 2 dB/cm improvement in line with that observed in literature. Waveguides fabricated on the SRN:D film are further shown to possess a nonlinear parameter of 95 W-1 m-1, with the film exhibiting a linear and nonlinear refractive index of 2.46 and 9.8 [Formula: see text] 10-18 m2W-1 respectively.

8.
Sci Rep ; 12(1): 9487, 2022 Jun 08.
Article in English | MEDLINE | ID: mdl-35676414

ABSTRACT

Supercontinuum generation is demonstrated in a 3-mm-long ultra-silicon-rich nitride (USRN) waveguide by launching 500 fs pulses centered at 1555 nm with a pulse energy of 17 pJ. The generated supercontinuum is experimentally characterized to possess a high spectral coherence, with an average |g12| exceeding 0.90 across the wavelength range of the coherence measurement (1260 nm to 1700 nm). Numerical simulations further indicate a high coherence over the full spectrum. The experimentally measured supercontinuum agrees well with the theoretical simulations based on the generalized nonlinear Schrödinger equation. The generated broadband spectra using 500 fs pulses possessing high spectral coherence provide a promising route for CMOS-compatible light sources for self-referencing applications, metrology, and imaging.

9.
BMC Womens Health ; 22(1): 116, 2022 04 12.
Article in English | MEDLINE | ID: mdl-35413905

ABSTRACT

OBJECTIVES: To evaluate the effect of intraperitoneal normal saline instillation (INSI) of 15 mL/kg body weight on postoperative pain after a gynaecological laparoscopic procedure. DESIGN: Randomised controlled trial. SETTING: University Hospital in Kuala Lumpur, Malaysia. PARTICIPANTS: Patients aged 18-55 years, with American Society of Anaesthesiologists (ASA) classification I-II, scheduled for an elective gynaecological laparoscopic procedure for a benign cause. INTERVENTION: The patients were randomly allocated to two groups. In the intervention group, 15 mL/kg body weight of normal saline was instilled intraperitoneally, while the control group received the conventional combination of open laparoscopic trocar valves with gentle abdominal pressure to remove the retained carbon dioxide. MAIN OUTCOME MEASURES: The outcomes measured were the mean pain scores for shoulder and upper abdominal pain at 24 h, 48 h, and 72 h postoperatively. RESULTS: A total of 68 women completed the study, including 34 women in each group. There was no difference in the shoulder pain score at 24 h, 48 h, and 72 h postoperatively. However, a significant improvement in the upper abdominal pain score after 48 h (95% confidence interval [CI] 0.34-1.52, p = 0.019) and 72 h (95% CI 0.19-0.26, p = 0.007) postoperatively were observed. CONCLUSIONS: INSI of 15 mL/kg body weight does not lower postoperative shoulder pain compared to no fluid instillation. A modest pain score improvement was observed in the upper abdominal area at 48 h and 72 h after surgery. An INSI of up to 30 mL/kg body weight may be required to eliminate shoulder pain. Care must be taken before administering a higher amount of INSI, considering the potential risk of peritoneal adhesions. Clinical registration ISRCTN Identifier: 87898051 (Date: 26 June 2019) https://doi.org/10.1186/ISRCTN87898051.


Subject(s)
Laparoscopy , Saline Solution , Abdominal Pain/etiology , Abdominal Pain/prevention & control , Anesthetics, Local , Body Weight , Double-Blind Method , Female , Humans , Laparoscopy/methods , Pain, Postoperative/etiology , Pain, Postoperative/prevention & control , Shoulder Pain/etiology , Shoulder Pain/prevention & control
10.
Sci Rep ; 12(1): 5267, 2022 Mar 28.
Article in English | MEDLINE | ID: mdl-35347190

ABSTRACT

Ultra-silicon-rich nitride with refractive indices ~ 3 possesses high nonlinear refractive index-100× higher than stoichiometric silicon nitride and presents absence of two-photon absorption, making it attractive to be used in nonlinear integrated optics at telecommunications wavelengths. Despite its excellent nonlinear properties, ultra-silicon-rich nitride photonics devices reported so far still have fairly low quality factors of [Formula: see text], which could be mainly attributed by the material absorption bonds. Here, we report low temperature plasma-deposited dichlorosilane-based ultra-silicon-rich nitride (Si8N) with lower material absorption bonds, and ~ 2.5× higher quality factors compared to ultra-silicon-rich nitride conventionally prepared with silane-based chemistry. This material is found to be highly rich in silicon with refractive indices of ~ 3.12 at telecommunications wavelengths and atomic concentration ratio Si:N of ~ 8:1. The material morphology, surface roughness and binding energies are also investigated. Optically, the material absorption bonds are quantified and show an overall reduction. Ring resonators fabricated exhibit improved intrinsic quality factors [Formula: see text], ~ 2.5× higher compared to conventional silane-based ultra-silicon-rich nitride films. This enhanced quality factor from plasma-deposited dichlorosilane-based ultra-silicon-rich nitride signifies better photonics device performance using these films. A pathway has been opened up for further improved device performance of ultra-silicon-rich nitride photonics devices at material level tailored by choice of different chemistries.

11.
Light Sci Appl ; 10(1): 130, 2021 Jun 18.
Article in English | MEDLINE | ID: mdl-34140461

ABSTRACT

Optical pulses are fundamentally defined by their temporal and spectral properties. The ability to control pulse properties allows practitioners to efficiently leverage them for advanced metrology, high speed optical communications and attosecond science. Here, we report 11× temporal compression of 5.8 ps pulses to 0.55 ps using a low power of 13.3 W. The result is accompanied by a significant increase in the pulse peak power by 9.4×. These results represent the strongest temporal compression demonstrated to date on a complementary metal-oxide-semiconductor (CMOS) chip. In addition, we report the first demonstration of on-chip spectral compression, 3.0× spectral compression of 480 fs pulses, importantly while preserving the pulse energy. The strong compression achieved at low powers harnesses advanced on-chip device design, and the strong nonlinear properties of backend-CMOS compatible ultra-silicon-rich nitride, which possesses absence of two-photon absorption and 500× larger nonlinear parameter than in stoichiometric silicon nitride waveguides. The demonstrated work introduces an important new paradigm for spectro-temporal compression of optical pulses toward turn-key, on-chip integrated systems for all-optical pulse control.

12.
IDCases ; 23: e01051, 2021.
Article in English | MEDLINE | ID: mdl-33532241

ABSTRACT

Preterm birth is a global concern with considerable morbidity and mortality. Intrapartum infection is a known cause of preterm birth and Actinomyces infection is one of the infections contributing to preterm birth. We report a case of preterm birth of a trisomy-21 neonate to a mother with positive Actinomyces naeslundii from an intra-operative placental swab sample and discussed the relationship of this bacteria and preterm delivery, and the role of postpartum antibiotics use in this case.

14.
Opt Express ; 27(16): 23549-23557, 2019 Aug 05.
Article in English | MEDLINE | ID: mdl-31510630

ABSTRACT

An 8-channel coarse wavelength division multiplexer (CWDM) based on coupled vertical gratings has been designed, fabricated and characterized. The devices are implemented on the ultra-silicon-rich nitride (USRN) platform. The demonstrated device possesses 8 CWDM channels. The absence of free spectral range (FSR) enabled the overall multiplexed bandwidth to span across the S + C + L bands. The CWDM channels meet the specifications stipulated by the International Telecommunications Union G.694.2 standard. The average channel crosstalk is -25dB. Pseudo-Random Bit Sequence 231-1 Non-Return-Zero data at 30Gb/s was launched into the device and a clear eye diagram was obtained. The device was further used with a USRN waveguide generating supercontinuum to create a multi-wavelength source emitting light at 8 CWDM wavelengths.

15.
ACS Sens ; 4(10): 2746-2753, 2019 10 25.
Article in English | MEDLINE | ID: mdl-31524375

ABSTRACT

Infrared gas sensors have been proven promising for broad applications in Internet of Things and Industrial Internet of Things. However, the lack of miniaturized light sources with good compatibility and tunable spectral features hinders their widespread utilization. Herein, a strategy is proposed to increase the radiated power from microelectromechanical-based thermal emitters by coating with graphene oxide (GO). The radiation can be substantially enhanced, which partially stems from the high emissivity of GO coating demonstrated by spectroscopic methods. Moreover, the sp2 structure within GO may induce plasmons and thus couple with photons to produce blackbody radiation and/or new thermal emission sources. As a proof-of-concept demonstration, the GO-coated emitter is integrated into a multifunctional monitoring platform and evaluated for gas detection. The platform exhibits sensitive and highly selective detection toward CO2 at room temperature with a detection limit of 50 ppm and short response/recovery time, outperforming the state-of-the-art gas sensors. This study demonstrates the emission tailorability of thermal emitters and the feasibility of improving the associated gas sensing property, offering perspectives for designing and fabricating high-end optical sensors with cost-effectiveness and superior performance.


Subject(s)
Carbon Dioxide/analysis , Graphite/chemistry , Acetone/analysis , Carbon Monoxide/analysis , Humidity , Infrared Rays , Methane/analysis , Spectroscopy, Fourier Transform Infrared , Temperature
16.
Sci Rep ; 9(1): 10364, 2019 Jul 17.
Article in English | MEDLINE | ID: mdl-31316096

ABSTRACT

The dispersive nonlinear refractive index of ultra-silicon-rich nitride, and its two-photon and three-photon absorption coefficients are measured in the wavelength range between 0.8 µm-1.6 µm, covering the O- to L - telecommunications bands. In the two-photon absorption range, the measured nonlinear coefficients are compared to theoretically calculated values with a simple parabolic band structure. Two-photon absorption is observed to exist only at wavelengths lower than 1.2 µm. The criterion for all-optical switching through the material is investigated and it is shown that ultra-silicon-rich nitride is a good material in the three-photon absorption region, which spans the entire O- to L- telecommunications bands.

17.
Asia Pac J Clin Nutr ; 27(6): 1161-1174, 2018.
Article in English | MEDLINE | ID: mdl-30485913

ABSTRACT

BACKGROUND AND OBJECTIVES: Malnutrition is under-recognized and under-treated in Asia due to resource constraints, lack of awareness and knowledge among healthcare professionals and patients, and lack of standardized procedures for malnutrition management. While international guidelines for the management of malnutrition are available, they may not be easily applicable to the patient population and healthcare settings within Southeast Asia. This paper provides consensus recommendations, developed by the Regional Nutrition Working Group, to foster evidence-based nutritional care in Southeast Asia to improve patient outcomes. METHODS AND STUDY DESIGN: The group convened and discussed evidence-based recommendations and clinical experiences in the management of malnutrition in hospitalized and community-dwelling adults, and the relevance of oral nutritional supplements in clinical practice. Supported by a literature search from January 2007-September 2017, consensus statements on key aspects of malnutrition management were developed. RESULTS: Malnutrition management should be considered as an integral part of patient care and managed by a multidisciplinary team. Hospitalized patients and outpatients should be screened for risk of malnutrition with validated tools. Nutrition intervention, including oral, enteral, or parenteral nutrition, should be accessible and individualized to all patients who are malnourished or at risk of malnutrition. Education on nutrition care is imperative for healthcare professionals, patients and caregivers. CONCLUSION: These consensus recommendations provide practical guidance to improve nutrition practice within healthcare in Southeast Asia. With collaborative efforts from the clinical community, professional societies and policy makers, this regional effort may also facilitate change in the nutrition practice at the institutional and national level.


Subject(s)
Consensus , Malnutrition/therapy , Nutrition Therapy/methods , Asia, Southeastern , Health Personnel/education , Hospitalization , Independent Living , Malnutrition/diagnosis , Nutritional Sciences/education , Practice Guidelines as Topic
18.
Appl Opt ; 56(17): 5086-5091, 2017 Jun 10.
Article in English | MEDLINE | ID: mdl-29047660

ABSTRACT

Electrically pumped heterogeneously integrated III-V/SiO2 semiconductor on-chip lasers with different types of etched facet reflectors are designed and fabricated and their lasing performances are characterized and compared. The III-V quantum-well-based epitaxial layers are bonded on silica-on-silicon substrates and fabricated to form Fabry-Perot lasers with dry-etched rear facets. Three types of reflectors are demonstrated, which are etched facets terminated by air, benzocyclobutene, and metal with a thin layer of SiO2 insulator in-between. The laser devices are characterized and compared, including lasing threshold, external quantum efficiency, and output power, and show the impact of different types of etched facet reflectors on lasing performance.

19.
Appl Opt ; 55(24): 6752-6, 2016 Aug 20.
Article in English | MEDLINE | ID: mdl-27556999

ABSTRACT

A graded-index multilayer thin-film stack is optimized to act as a cladding layer on top of a silicon (Si) nanowaveguide and also a collimator for chip coupling where the waveguide ends. The numerical example shows an optimized graded-index profile from 2.35 to 1.45 provides an optical coupling to the standard single-mode fiber with efficiency close to 90% while retaining tight light confinement for the Si nanowaveguide. The corresponding material realization of a graded-index profile with a Si-rich nitride SiNx/SiON/SiO2 system is explored using inductively coupled plasma chemical vapor deposition, and a SiNx cladded Si waveguide is demonstrated.

20.
Opt Lett ; 41(13): 3149-52, 2016 Jul 01.
Article in English | MEDLINE | ID: mdl-27367124

ABSTRACT

We design and demonstrate optically pumped microlasers with a hetero-core cavity formed by III-V and silicon-on-insulator (SOI) materials. Hetero-core cavities with identical lateral dimension are fabricated. The cavity is formed by III-V layer with thickness of 210 nm on top of SOI layer with thickness of 300 nm via SiO2 interlayer wafer bonding. Continuous wave laser operation is achieved for a diameter down to 2 µm with a corresponding mode volume of 0.07λ3 and quality factor of 1.3×104. The architecture renders an alternative laser structure for heterogeneous laser-on-chip, with no dedicated vertical coupling mechanism needed between the two materials' layers.

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