Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 34
Filter
1.
Antimicrob Resist Infect Control ; 12(1): 52, 2023 05 30.
Article in English | MEDLINE | ID: mdl-37254192

ABSTRACT

BACKGROUND: The Asia Pacific Society of Infection Control launched the APSIC guide for prevention of catheter associated urinary tract infections in July 2022. It aims to highlight practical recommendations in a concise format designed to assist healthcare facilities in the Asia Pacific region to achieve high standards in infection prevention and control practices during the management and care of patients with a urinary catheter. METHODS: The guidelines were developed by an appointed workgroup comprising experts in the Asia Pacific region, following reviews of previously published guidelines and recommendations relevant to each section. RESULTS: It recommends that healthcare institutions have a catheter associated urinary tract infection prevention program that includes surveillance and the use of the insertion and maintenance bundles. Implementation of the bundles is best done using a quality improvement approach with a multidisciplinary team. CONCLUSIONS: Healthcare facilities should aim for excellence in care of patients with urinary catheters. It is recommended that healthcare facilities have a catheter associated urinary tract infection prevention program as part of their Infection Prevention and Control program.


Subject(s)
Catheter-Related Infections , Urinary Tract Infections , Humans , Catheter-Related Infections/prevention & control , Catheter-Related Infections/epidemiology , Infection Control , Urinary Catheterization/adverse effects , Urinary Tract Infections/prevention & control , Urinary Tract Infections/epidemiology , Urinary Catheters/adverse effects
2.
Antimicrob Resist Infect Control ; 12(1): 53, 2023 05 30.
Article in English | MEDLINE | ID: mdl-37254208

ABSTRACT

BACKGROUND: The Asia Pacific Society of Infection Control launched the Infection Prevention and Control Guidelines in July 2022. This document describes the guidelines and recommendations for safe practices in dental setting. It aims to highlight practical recommendations in a concise format designed to assist dental facilities at Asia Pacific region in achieving high standards in infection prevention and control practices, staff and patient safety. METHOD: The guidelines were developed by an appointed workgroup comprising experts in the Asia Pacific region, following reviews of previously published international guidelines and recommendations relevant to each section. RESULTS: It recommends standard precautions as a minimal set of preventive measures to protect staff and prevent cross transmission. Surgical aseptic technique is recommended when procedures are technically complex and longer in duration. Only trained staff are eligible to conduct reprocessing of dental instruments. The design, layout of the dental facility are important factors for successful infection prevention. The facility should also have a Pandemic Preparedness Plan. CONCLUSIONS: Dental facilities should aim for excellence in infection prevention and control practices as this is part of patient safety. The guidelines that come with a checklist help dental facilities to identify gaps for improvement to reach this goal.


Subject(s)
Infection Control , Patient Safety , Humans , Infection Control/methods , Asia
3.
Environ Res ; 210: 112953, 2022 07.
Article in English | MEDLINE | ID: mdl-35182590

ABSTRACT

In wastewater monitoring, detecting extremely high pollutant concentrations is necessary to properly calibrate the treatment process. However, existing hardware sensors have a limited linear range which may fail to measure extremely high levels of pollutants; and likewise, the conventional "soft" model sensors are not suitable for the highly-skewed data distributions either. This study developed a new soft sensor by using eXtreme Gradient Boosting (XGBoost) machine learning to 'measure' the wastewater organics (in terms of 5-day biochemical oxygen demand (BOD5)). The soft sensor was tested on influent and effluent BOD5 of two different wastewater treatment plants to validate the results. The model results showed that XGBoost can detect these extreme values better than conventional soft sensors. This new soft sensor can function using a sparse input matrix via XGBoost's sparsity awareness algorithm - which can address the limitation of the conventional soft sensor with the fallibility of supporting hardware sensors even.


Subject(s)
Wastewater , Water Purification
4.
Genesis ; 55(12)2017 12.
Article in English | MEDLINE | ID: mdl-29115049

ABSTRACT

Two estrogen receptors, ESR1 and ESR2, are responsible for the classical actions of estrogens in mammalian species. They display different spatiotemporal expression patterns and nonoverlapping functions in various tissues and physiological conditions. In this study, a novel knock-in mouse line that expresses codon-improved Cre recombinase (iCre) under regulation of the natural Esr1 promoter (Esr1-iCre) was developed. Functional characterization of iCre expression by crossing them with reporter lines (ROSA26-lacZ or Ai9-RFP) showed that iCre is faithfully expressed in Esr1-lineage cells. This novel transgenic mouse line will be a useful animal model for lineage-tracing Esr1-expressing cells, selective gene ablation in the Esr1-lineage cells and for generating global Esr1 knockout mice.


Subject(s)
Estrogen Receptor alpha/genetics , Estrogens/genetics , Integrases/genetics , Animals , Cell Lineage/genetics , Estrogens/metabolism , Gene Expression Regulation, Developmental , Gene Knock-In Techniques , Mice , Mice, Knockout , Mice, Transgenic/genetics , Promoter Regions, Genetic
5.
Diabetes ; 62(5): 1763-7, 2013 May.
Article in English | MEDLINE | ID: mdl-23300277

ABSTRACT

Evidence is limited as to whether heritable risk of obesity varies throughout adulthood. Among >34,000 European Americans, aged 18-100 years, from multiple U.S. studies in the Population Architecture using Genomics and Epidemiology (PAGE) Consortium, we examined evidence for heterogeneity in the associations of five established obesity risk variants (near FTO, GNPDA2, MTCH2, TMEM18, and NEGR1) with BMI across four distinct epochs of adulthood: 1) young adulthood (ages 18-25 years), adulthood (ages 26-49 years), middle-age adulthood (ages 50-69 years), and older adulthood (ages ≥70 years); or 2) by menopausal status in women and stratification by age 50 years in men. Summary-effect estimates from each meta-analysis were compared for heterogeneity across the life epochs. We found heterogeneity in the association of the FTO (rs8050136) variant with BMI across the four adulthood epochs (P = 0.0006), with larger effects in young adults relative to older adults (ß [SE] = 1.17 [0.45] vs. 0.09 [0.09] kg/m², respectively, per A allele) and smaller intermediate effects. We found no evidence for heterogeneity in the association of GNPDA2, MTCH2, TMEM18, and NEGR1 with BMI across adulthood. Genetic predisposition to obesity may have greater effects on body weight in young compared with older adulthood for FTO, suggesting changes by age, generation, or secular trends. Future research should compare and contrast our findings with results using longitudinal data.


Subject(s)
Aging , Obesity/genetics , Polymorphism, Single Nucleotide , Proteins/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Alpha-Ketoglutarate-Dependent Dioxygenase FTO , Body Mass Index , Cohort Studies , Cross-Sectional Studies , Female , Genetic Association Studies , Health Surveys , Humans , Male , Middle Aged , Obesity/metabolism , Proteins/metabolism , United States , White People , Young Adult
6.
Nanoscale ; 5(3): 961-70, 2013 Feb 07.
Article in English | MEDLINE | ID: mdl-23238167

ABSTRACT

Metal-assisted Chemical Etching of silicon has recently emerged as a powerful technique to fabricate 1D, 2D, and 3D nanostructures in silicon with high feature fidelity. This work demonstrates that out-of-plane rotational catalysts utilizing polymer pinning structures can be designed with excellent control over rotation angle. A plastic deformation model was developed establishing that the catalyst is driven into the silicon substrate with a minimum pressure differential across the catalyst thickness of 0.4-0.6 MPa. Force-displacement curves were gathered between an Au tip and Si or SiO(2) substrates under acidic conditions to show that Derjaguin and Landau, Verwey and Overbeek (DLVO) based forces are capable of providing restorative forces on the order of 0.2-0.3 nN with a calculated 11-18 MPa pressure differential across the catalyst. This work illustrates that out-of-plane rotational structures can be designed with controllable rotation and also suggests a new model for the driving force for catalyst motion based on DLVO theory. This process enables the facile fabrication of vertically aligned thin-film metallic structures and scalloped nanostructures in silicon for applications in 3D micro/nano-electromechanical systems, photonic devices, nanofluidics, etc.


Subject(s)
Metal Nanoparticles/chemistry , Metal Nanoparticles/ultrastructure , Models, Chemical , Models, Molecular , Catalysis , Elastic Modulus , Motion , Rotation , Stress, Mechanical , Surface Properties
7.
Nano Lett ; 11(6): 2369-74, 2011 Jun 08.
Article in English | MEDLINE | ID: mdl-21526791

ABSTRACT

In recent years metal-assisted chemical etching (MaCE) of silicon, in which etching is confined to a small region surrounding metal catalyst templates, has emerged as a promising low cost alternative to commonly used three-dimensional (3D) fabrication techniques. We report a new methodology for controllable folding of 2D metal catalyst films into 3D structures using MaCE. This method takes advantage of selective patterning of the catalyst layer into regions with mismatched characteristic dimensions, resulting in uneven etching rates along the notched boundary lines that produce hinged 2D templates for 3D folding. We explore the dynamics of the folding process of the hinged templates, demonstrating that the folding action combines rotational and translational motion of the catalyst template, which yields topologically complex 3D nanostructures with intimately integrated metal and silicon features.


Subject(s)
Gold/chemistry , Metal Nanoparticles/chemistry , Silicon/chemistry , Catalysis , Particle Size , Surface Properties
8.
Adv Mater ; 23(5): 659-63, 2011 Feb 01.
Article in English | MEDLINE | ID: mdl-21274916

ABSTRACT

A process that allows control over the 3D motion of catalyst nanostructures during metal-assisted chemical etching by their local pinning prior to etching is demonstrated. The pinning material acts as a fulcrum for rotation of the catalyst structures resulting in etching of silicon features with rotational geometry.


Subject(s)
Microtechnology/methods , Molecular Conformation , Nanotechnology/methods , Silicon/chemistry , Microscopy, Electron, Scanning , Surface Properties
9.
J Hosp Infect ; 74(4): 358-64, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20153548

ABSTRACT

We assessed the risk factors and molecular epidemiology of multidrug-resistant Acinetobacter baumannii (MDR-AB) in Hong Kong. The patients were treated in five hospitals in a healthcare region during 2005-2006. We performed genomic identification by amplified rRNA gene restriction analysis (ARDRA) and investigated the existence of metallo-beta-lactamases and the clonality of representative MDR-AB strains by phenotypic and molecular methods. Forty-five subjects with MDR-AB were compared with 135 controls (patients with no MDR-AB). In the logistic regression, chronic wound (odds ratio: 29.5, 95% confidence interval: 8.1-107.2; P<0.001) was the only factor independently associated with MDR-AB colonisation or infection. ARDRA identified all 45 MDR-AB as genomic species 2TU. Pulsed-field gel electrophoresis clustered all except two isolates into two clonal types, designated HKU1 and HKU2 with 24 and 19 isolates, respectively. The main features of HKU1 strains were ST26, adeB type XII, positivity for bla(OxA-23-like) and bla(OxA-51-like) genes and high level resistance to carbapenems. Most HKU1 strains retained susceptibility to gentamicin, cotrimoxazole and minocycline. By contrast, HKU2 strains exhibited ST22, adeB type II, and were usually positive only for the bla(OxA-51-like) gene and resistant to gentamicin, cotrimoxazole and minocycline. Both clones were found to have disseminated widely. In conclusion, clonal expansion is playing major roles in the increase of MDR-AB in these hospitals in Hong Kong. The findings highlight the need to enhance infection control measures.


Subject(s)
Acinetobacter Infections/epidemiology , Acinetobacter baumannii/classification , Acinetobacter baumannii/drug effects , Anti-Bacterial Agents/pharmacology , Bacterial Typing Techniques , Cross Infection/epidemiology , Drug Resistance, Multiple, Bacterial , Acinetobacter Infections/microbiology , Acinetobacter baumannii/isolation & purification , Aged , Aged, 80 and over , Cluster Analysis , Cross Infection/microbiology , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Electrophoresis, Gel, Pulsed-Field , Female , Health Facilities , Hong Kong/epidemiology , Humans , Male , Middle Aged , Molecular Sequence Data , Polymorphism, Restriction Fragment Length , Risk Factors , Wound Infection/epidemiology , Wound Infection/microbiology
10.
Eur J Clin Microbiol Infect Dis ; 28(12): 1447-56, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19727869

ABSTRACT

The antimicrobial stewardship program (ASP) is a major strategy to combat antimicrobial resistance and to limit its expenditure. We have improved on our existing ASP to implement a sustainable and cost-effective two-stage immediate concurrent feedback (ICF) model, in which the antimicrobial prescription is audited by two part-time infection control nurses at the first stage, followed by "physician ICF" at the second stage. In January 2005, an ASP focused on broad-spectrum intravenous antibiotics was implemented. All in-patients, except from the intensive care, bone marrow transplantation, liver transplantation, pediatric, and private units, being treated with broad-spectrum intravenous antibiotics were included. The compliance to ICF and "physician ICF", antibiotics usage density measured by expenditure and defined daily doses (DDD) were recorded and analyzed before and after the ASP. The overall conformance rate to antibiotic prescription guidelines was 79.4%, while the conformance to ICF was 83.8%. Antibiotics consumption reduced from 73.06 (baseline, year 2004) to 64.01 (year 2007) per 1,000 patient bed-day-occupancy. Our model can be easily applied even in the clinical setting of limited resources.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Bacterial Infections/drug therapy , Drug Utilization/standards , Prescriptions/standards , Attitude of Health Personnel , Bacterial Infections/diagnosis , Guideline Adherence/statistics & numerical data , Health Services Research , Hospitals , Humans , Organizational Policy
11.
Infection ; 37(4): 320-33, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19636497

ABSTRACT

BACKGROUND: Hand hygiene promotion for patient safety is a challenge worldwide, and local data are critical to tailor strategies to the setting. METHODS: This is a cross-sectional study of nurses and physicians providing direct patient care in four hospitals in Hong Kong using an anonymous questionnaire survey. Cognitive factors related to hand hygiene and the perception of effective interventions promoting hand hygiene were assessed. RESULTS: The overall response rate was 59.3%. Among respondents, 70% of the nurses and 49% of the physicians perceived that over 15% of patients would suffer from healthcare-associated infections. A total of 79% of the nurses and 68% of the physicians believed that more than 5% of patients would die as a result of healthcare-associated infection. A total of 60% of the nurses and 46% of the physicians acknowledged that over 75% of healthcare-associated infections could be prevented by optimal hand hygiene practices, although 36% of the nurses and 23% of the physicians claimed that six to ten hand cleansing times per hour would be necessary. Bivariate analysis showed significant differences between professionals in self-reported performance. A multivariate regression model revealed that perceived behavioral control and subjective norms were the most important factors associated with the nurses and physicians' self-reported hand hygiene performance. However when gender was taken into account among professionals, subjective norms was the only consistent one. CONCLUSION: These results could be used as a tool to create goal-specific strategies for motivating hand hygiene amongst nurses and physicians in Hong Kong, with appropriate promotional interventions delivered to the different professional groups and specialties.


Subject(s)
Attitude of Health Personnel , Cross Infection/prevention & control , Guideline Adherence/statistics & numerical data , Hand Disinfection , Health Knowledge, Attitudes, Practice , Adult , Cross-Sectional Studies , Female , Hong Kong , Hospitals , Humans , Male , Middle Aged , Nurses , Physicians , Surveys and Questionnaires , Young Adult
12.
Anaesth Intensive Care ; 36(2): 180-4, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18361008

ABSTRACT

We aimed to identify and categorise advanced communication skills used by experienced consultant paediatric anaesthetists to facilitate the induction of paediatric anaesthesia. The communication techniques were both verbal and non-verbal. Communications with potentially negative effects were also noted. Eighty-three inductions were observed over a three-month period. The 12 anaesthetists observed were all senior consultants at a tertiary referral paediatric centre. The mean age of patients was 6.1 years SD+/-4.8. There were 53 males (63.9%) and 30 females (36.1%). A first anaesthetic was administered to 43 patients (56%) and sedative premedication to six (8%). Inhalational inductions were observed in 59 patients (71%). The remainder received an intravenous induction. Anaesthesia was induced in the operating room on 68 occasions (82%), in the induction room on 11 (13%) and in the radiology department on 4(5%). The most common communication techniques used were: voice change in 60 (72%); distraction in 49 (59%); direct commands in 39 (47%); repetition in 34 (41%); imagery in 21 (25%) and focused attention 21 (25%). Other techniques used were seeding of ideas, utilisation, non-verbal cues, double-binds, story-telling, indirect suggestion, dissociation and reversed effect. Sabotage by parents or staff such as inadvertent negative suggestions, was observed on 14 occasions (17%). Paediatric anaesthetists utilise a wide range of communication techniques in a highly flexible manner when inducing anaesthesia in children. Many of these communications can be characterised as hypnotherapeutic. Our observations suggest that formal structured training in communication skills and further research is warranted.


Subject(s)
Anesthesia , Communication , Adolescent , Anesthesia, Inhalation , Anesthesia, Intravenous , Child , Child, Preschool , Cues , Female , Humans , Infant , Male , Nonverbal Communication
13.
Eur Respir J ; 31(5): 998-1004, 2008 May.
Article in English | MEDLINE | ID: mdl-18216063

ABSTRACT

Small airways are the major site of airflow obstruction in chronic obstructive pulmonary disease (COPD). This is attributed to loss of elastin in alveoli and fibrosis in small airways. In the present study, it was hypothesised that changes to elastic fibres in alveoli might be paralleled by a similar reduction in elastic fibres in small airways. Tissue blocks from patients who had lobectomy for bronchial carcinoma were studied. Patients were classified as COPD (forced expiratory volume in one second (FEV(1)) < 80% predicted, FEV(1)/forced vital capacity (FVC) < 0.7) or controls (FEV(1) > or = 80% pred, FEV(1)/FVC > or = 0.7). Elastic fibres were visualised using Elastic van Gieson staining and the volume fraction (v/f) of elastic fibres was determined as a percentage of tissue volume using point counting. Elastic fibre networks were also visualised by confocal microscopy. The v/f for elastic fibres in alveoli was 18.6% for COPD and 32.8% in controls. In the airways the v/f was 14.6% for COPD and 25.5% in controls. FEV(1)% predicted was correlated with v/f in both alveoli and small airways. The volume fraction of elastic fibres was reduced to a similar extent in small airways and alveoli in chronic obstructive pulmonary disease and both were correlated with the extent of airflow obstruction. Loss of elastic fibres in small airways may contribute to the development of airflow obstruction in chronic obstructive pulmonary disease.


Subject(s)
Bronchi/pathology , Elastic Tissue/pathology , Pulmonary Alveoli/pathology , Pulmonary Disease, Chronic Obstructive/pathology , Aged , Case-Control Studies , Female , Forced Expiratory Volume , Humans , Male , Middle Aged , Respiratory Function Tests , Vital Capacity
14.
Hong Kong Med J ; 12(2): 141-8, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16603782

ABSTRACT

OBJECTIVE: To discuss the implementation of an 'antimicrobial stewardship programme' as a means to improve the quality of antimicrobial use in a hospital setting in Hong Kong. PARTICIPANTS: Consensus working group on 'antimicrobial stewardship programme', The Scientific Committee on Infection Control, Centre for Health Protection, Department of Health, comprised 11 experts. The remit of the working group was to discuss the rationale and requirement for optimising antimicrobial prescriptions in hospitals by the introduction of an 'antimicrobial stewardship programme'. EVIDENCE: PubMed articles, national and international guidelines, and abstracts of international meetings published between January 2000 and December 2004 on programmes for improving the use of antimicrobials in hospitals. Only English medical literature was reviewed. CONSENSUS PROCESS: Data search was performed independently by three members of the working group. They met on three occasions before the meeting to discuss all collected articles. A final draft was circulated to the working group before a meeting on 3 January 2005. Five commonly asked questions about an 'antimicrobial stewardship programme' were selected for discussion by the participants. Published information on the rationale, components, outcome measures, advantages, and disadvantages of the programme was reviewed. Recent unpublished data from local studies of an 'antimicrobial stewardship programme' were also discussed. The timing, potential problems, and practical issues involved in the implementation of an 'antimicrobial stewardship programme' in Hong Kong were then considered. The consensus statement was circulated to and approved by all participants. CONCLUSION: The continuous indiscriminate and excessive use of antimicrobial agents promotes the emergence of antibiotic-resistant organisms. Antimicrobial resistance substantially raises already-rising health care costs and increases patient morbidity and mortality. Pattern of prescriptions in hospitals can be improved through the implementation of an 'antimicrobial stewardship programme'. A 'universal' and 'continuous' 'antimicrobial stewardship programme' should now be established in Hong Kong hospitals.


Subject(s)
Anti-Infective Agents/administration & dosage , Drug Utilization Review/organization & administration , Drug Utilization/standards , Guideline Adherence/organization & administration , Infection Control/standards , Pharmacy Service, Hospital/standards , Practice Guidelines as Topic , Drug Resistance , Hong Kong , Humans , Infection Control/organization & administration , Program Development , Quality Assurance, Health Care
15.
J Arthroplasty ; 18(6): 714-8, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14513443

ABSTRACT

We analyzed the wound infection rate of 1,367 primary total hip and knee arthroplasties performed between 1991 and 1999. Two hundred and fifteen arthroplasties were performed with 3 doses (3 x 750 mg) of cefuroxime, and 1,152 arthroplasties were performed with a single preoperative dose (1 x 1 g) of cefazolin as antimicrobial prophylaxis. All wound infections that occurred within 2 years of the index surgery were analyzed. The deep wound infection rate of total hip arthroplasty was 1.1% (95% confidence interval [CI], 0%-3.3%) in the cefuroxime group and 1.1% (95% CI, 0%-2.2%) in the cefazolin group (Fisher's exact test, P = 1.0). The deep wound infection rate of total knee arthroplasty in the cefuroxime group (1.6%; 95% CI, 0%-3.8%) was not significantly different from the cefazolin group (1.0%; 95% CI, 0.3%-1.7%) (Fisher's exact test, P =.63). We concluded that a single dose (1 g) of cefazolin given at anesthetic induction offered similar protection to 3 doses (3 x 750 mg) of cefuroxime in preventing infection in primary total joint arthroplasty.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Antibiotic Prophylaxis , Arthroplasty, Replacement , Cefazolin/administration & dosage , Surgical Wound Infection/prevention & control , Aged , Cefuroxime/administration & dosage , Female , Humans , Male , Middle Aged , Surgical Wound Infection/epidemiology , Treatment Outcome
16.
J Cardiovasc Surg (Torino) ; 44(2): 217-21, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12813387

ABSTRACT

Patients with porcelain aorta and severe calcification of the great vessels are a challenging dilemma for the cardiovascular surgeon regarding bypass technique, choice of conduit, and selection of proximal anastomotic sites due to the high incidence of devastating thromboembolization and aortic injury. No currently proposed surgical approach avoids manipulation of the heavily calcified ascending aorta. Three patients presented with unstable angina and decreased ventricular function secondary to significant left main coronary artery stenosis and 3-vessel coronary artery disease. In addition to the coronary artery disease, severely calcified ascending aorta and great vessels were discovered. One patient presented with near total distal abdominal aortic occlusion, severe peripheral vascular disease, history of stroke, and carotid endarterectomy. Surgical coronary revascularization was indicated. Coronary artery bypass grafting using internal thoracic artery and greater saphenous vein composite arterial inflow grafts in combination with off-pump beating heart surgery was successfully used. Cardiopulmonary bypass and clamping of the aorta was avoided. No new neurologic deficit was observed. Coronary revascularization with internal thoracic artery composite grafts and avoiding cardiopulmonary bypass and clamping the calcified aorta is an effective method to prevent clamp injury and thromboembolization. Off-pump coronary artery bypass grafting seems to be an ideal indication in patients with porcelain aorta because the surgical techniques of "no-touch" and "no-cannulation" can be applied.


Subject(s)
Aorta/surgery , Calcinosis/surgery , Coronary Artery Bypass/methods , Coronary Vessels/pathology , Aged , Anastomosis, Surgical , Female , Humans , Male , Mammary Arteries/surgery , Saphenous Vein/surgery
17.
J Acoust Soc Am ; 110(5 Pt 1): 2567-74, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11757946

ABSTRACT

This paper describes a novel application of multiresolution analysis (MRA) in extracting acoustic features that possess de-noising capability for robust speech recognition. The MRA algorithm is used to construct a mel-scaled wavelet packet filter-bank, from which subband powers are computed as the feature parameters for speech recognition. Wiener filtering is applied to a few selected subbands at some intermediate stages of decomposition. For high-frequency bands, Wiener filters are designed based on a reduced fraction of the estimated noise power, making the consonant features much more prominent and contrastive. The proposed method is evaluated in phone recognition experiments with the TIMIT database. In the presence of stationary white noise at 10-dB SNR, the de-noised MRA features attain a phone recognition rate of 32%. There is a noticeable improvement compared with the accuracy of 29% and 20% attained by the commonly used mel-frequency cepstral coefficients (MFCC) with and without cepstral mean normalization (CMN), respectively. The effectiveness of the MRA features is also verified by the fact that they exhibit smaller distortion from clean speech.


Subject(s)
Attention , Hearing Aids , Noise , Speech Acoustics , Speech Reception Threshold Test , Humans , Markov Chains , Sound Spectrography
18.
Am J Public Health ; 90(10): 1526-9, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11029982

ABSTRACT

Country-specific activity and coverage data were used to estimate the childhood mortality impact (deaths averted) and costs of integrating vitamin A supplements into immunization campaigns conducted in 1998 and 1999. More than 94 million doses of vitamin A were administered in 41 countries in 1998, helping to avert nearly 169,000 deaths. During 1999, delivery of more than 97 million doses in 50 countries helped avert an estimated 242,000 deaths. The estimated incremental cost per death averted was US$72 (range: 36-142) in 1998 and US$64 (range: 32-126) in 1999. The estimated average total cost of providing supplementation per death averted was US$310 (range: 157-609) in 1998 and US$276 (range: 139-540) in 1999. Costs per death averted varied by campaign, depending on the number and proportion of the child population reached, number of doses received per child, and child mortality rates.


Subject(s)
Dietary Supplements , Vitamin A Deficiency/mortality , Vitamin A/administration & dosage , Child, Preschool , Developing Countries , Humans , Immunization Programs/organization & administration , Infant , Infant Mortality , Primary Prevention , Risk Factors , United Nations , Vitamin A/economics , Vitamin A Deficiency/drug therapy , Vitamin A Deficiency/epidemiology , World Health Organization
19.
J Infect Dis ; 181 Suppl 1: S55-9, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10657191

ABSTRACT

Diphtheria reappeared in Lithuania in 1986 and rose to epidemic levels by 1992. Between 1991 and 1996, 110 cases of diphtheria were registered, with an incidence of 0.03-1.15/100,000 population. Most cases (84%) and all 17 deaths occurred among persons >/=15 years, most of whom had never been vaccinated. Persons 40-49 years old had the highest average annual age-specific morbidity (1.70/100,000) and mortality (0.53/100,000) rates. Low levels of immunity among individuals 40-49 years old and migration to epidemic areas in Russia and Belarus contributed to the epidemic's occurrence. Between 1991 and 1995, toxigenic Corynebacterium diphtheriae strains were isolated from 84 of all registered patients (76%), and nontoxigenic strains were isolated from 13 (12%). By 1996, two mass vaccination campaigns, which provided one dose of vaccine to individuals 25-30 years old and three doses of vaccine to persons 31-60 years old, helped reduce the number of cases. The first campaign achieved 69% coverage; the second achieved 48% coverage.


Subject(s)
Diphtheria/epidemiology , Diphtheria/prevention & control , Disease Outbreaks , Immunization Programs , Adult , Child , Child, Preschool , Corynebacterium diphtheriae/immunology , Corynebacterium diphtheriae/isolation & purification , Diphtheria/microbiology , Diphtheria/mortality , Diphtheria Toxoid/administration & dosage , Diphtheria-Tetanus Vaccine , Diphtheria-Tetanus-Pertussis Vaccine/administration & dosage , Disease Notification/statistics & numerical data , Disease Outbreaks/prevention & control , Humans , Immunization Schedule , Incidence , Infant , Lithuania/epidemiology , Middle Aged , National Health Programs , Tetanus Toxoid/administration & dosage , Vaccines, Combined/administration & dosage
20.
J Infect Dis ; 181 Suppl 1: S60-4, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10657192

ABSTRACT

After nearly two decades without a diphtheria case in Latvia, the disease reappeared in 1986. From 1990 to 1996, case counts were highest among adults 40-49 years of age, school-aged children, and adolescents. Nonetheless, the average annualized incidence of disease was highest among infants and preschoolers. In August 1995, mass vaccination efforts began to provide adults 25-60 years of age with at least one dose of vaccine. By the end of the year, a 77% coverage rate was achieved, resulting in a decrease of reported diphtheria cases by 1996. From February to September 1997, special outreach efforts were focused on hard-to-reach populations; as a result, by June 1997, 55% of adults had received three doses of vaccine. While decreases in the incidence of and morbidity from diphtheria have occurred, additional efforts still need to be concentrated on improving vaccination coverage in adults and children <2 years of age and in reducing mortality from diphtheria.


Subject(s)
Diphtheria/epidemiology , Diphtheria/prevention & control , Disease Outbreaks , Immunization Programs , Adolescent , Adult , Age Distribution , Child , Child, Preschool , Corynebacterium diphtheriae/immunology , Corynebacterium diphtheriae/isolation & purification , Diphtheria/microbiology , Diphtheria Toxoid/administration & dosage , Disease Notification/statistics & numerical data , Disease Outbreaks/prevention & control , Humans , Immunization/statistics & numerical data , Incidence , Infant , Infant, Newborn , Latvia/epidemiology , Middle Aged , National Health Programs
SELECTION OF CITATIONS
SEARCH DETAIL
...