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1.
J Appl Microbiol ; 125(4): 1076-1093, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29907994

ABSTRACT

AIM: The aim of this study was to isolate and identify lipolytic bacteria. Perform a statistical stepwise physicochemical optimization for maximum production of extracellular lipase and its validation in a bioreactor. METHODS AND RESULTS: Several lipolytic bacteria were isolated from petroleum hydrocarbon-polluted soil. The strain expressing the highest lipase activity (47 U ml-1 ) was genetically identified as Gram-positive Bacillus stratosphericus PSP8 (NCBI GenBank accession no. MH120423). The response surface methodology (RSM)-central composite face centre (CCF) design of experiments was performed based on the preselected levels of the studied parameters obtained from the performed one-factor-at-a-time sequential experiments. A second-order polynomial model was predicted and improved the lipase production by approximately 1·6-fold. Preliminary scaling up of the validated optimized process was carried out in a batch 10-l stirred tank bioreactor, applying the optimum predicted operating conditions; pH 6·98, 34·8°C, 2·2 × 106 cells per ml, 200 rev min-1 , 4·82 g l-1 tributyrine concentration, 1% sucrose and 0·1% yeast extract. This yielded 89 U ml-1 at the late log phase of bacterial growth (48 h). Logistic kinetic model effectively characterized the submerged fermentation process, and the maximum specific growth and lipase production rates were estimated to be 0·338 and 0·164 h-1 respectively. CONCLUSIONS: The mesophilic and neutrophilic B. stratosphericus PSP8 isolated from petroleum hydrocarbon-contaminated soil is a proper source of lipase. The closeness of the predicted response with that of the experimental value and the enhancement of lipase productivity in fermenter scale by approximately 1·9-fold, showed that statistically optimized design can be used in order to improve the lipase production to meet the increasing demand. SIGNIFICANCE AND IMPACT OF THE STUDY: The RSM-CCF statistical optimization is useful for optimizing a large number of variables and studying their interactive effects on extracellular lipase production.


Subject(s)
Bacillus/enzymology , Bacterial Proteins/metabolism , Lipase/metabolism , Bacillus/chemistry , Bacillus/genetics , Bacillus/isolation & purification , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Bioreactors/microbiology , Fermentation , Kinetics , Lipase/chemistry , Lipase/genetics , Models, Statistical , Petroleum/analysis , Soil Microbiology
2.
Article | WPRIM (Western Pacific) | ID: wpr-780679

ABSTRACT

@# Measuring discomfort towardthe car seat is important as the act of driving requires a driver to remain at the car seat while controlling the car. The seat condition, including sitting position as well as the driver’s posture can lead to discomfort and fatigue. The objective of this study is to investigate a driver’s pressure distribution in static and dynamic circumstances for two types of cars; the sedan and compact car. This study involved both subjective and objective evaluations of 12 respondents. For the subjective evaluation, the Visual Analog Scales (VAS) were used to obtain respondents' perception of discomfort. For the objective evaluation, pressure distribution readings of the seat interface were obtained using piezo capacitive sensors. The findings showed that the highest pressure was recorded for the compact car. Furthermore, the static circumstance showed greater pressure compared to the dynamic state. Subjective evaluation indicated that the right buttocks and the lower back (lumbar)experience the highest discomfort for both types of seats.The type of seat found to contribute to the value of different pressure. Thus, it can be concluded that appropriate seat selection can reduce pressure as well as discomfort.


Subject(s)
Pressure
3.
Biosystems ; 146: 60-76, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27178784

ABSTRACT

Swarm robotics is concerned with the decentralised coordination of multiple robots having only limited communication and interaction abilities. Although fault tolerance and robustness to individual robot failures have often been used to justify the use of swarm robotic systems, recent studies have shown that swarm robotic systems are susceptible to certain types of failure. In this paper we propose an approach to self-healing swarm robotic systems and take inspiration from the process of granuloma formation, a process of containment and repair found in the immune system. We use a case study of a swarm performing team work where previous works have demonstrated that partially failed robots have the most detrimental effect on overall swarm behaviour. We have developed an immune inspired approach that permits the recovery from certain failure modes during operation of the swarm, overcoming issues that effect swarm behaviour associated with partially failed robots.


Subject(s)
Algorithms , Artificial Intelligence , Immune System/immunology , Robotics , Animals , Chemokines/immunology , Computer Simulation , Granuloma/immunology , Humans , Macrophages/immunology , Models, Immunological , T-Lymphocytes/immunology
4.
J Nutr ; 144(3): 375-81, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24500936

ABSTRACT

Few data on iodine status in Somalia are available, but it is assumed that deficiency is a public health problem due to the limited access to iodized salt. We aimed to describe the iodine status of the population of Somalia and to investigate possible determinants of iodine status. A national 2-stage, stratified household cluster survey was conducted in 2009 in the Northwest, Northeast, and South Central Zones of Somalia. Urinary iodine concentration (UIC) was determined in samples from women (aged 15-45 y) and children (aged 6-11 y), and examination for visible goiter was performed in the Northwest and South Central strata. A 24-h household food-frequency questionnaire was conducted, and salt samples were tested for iodization. The median UICs for nonpregnant women and children were 329 and 416 µg/L, respectively, indicating excessive iodine intake (>300 µg/L). The prevalence of visible goiter was <4%. The coverage of salt iodization was low, with a national average of 7.7% (95% CI: 3.2%, 17.4%). Spatial analysis revealed localized areas of relatively high and low iodine status. Variations could not be explained by food consumption or salt iodization but were associated with the main source of household drinking water, with consumers of borehole water having a higher UIC (569 vs. 385 µg/L; P < 0.001). Iodine intake in Somalia is among the highest in the world and excessive according to WHO criteria. Further work is required to investigate the geochemistry and safety of groundwater sources in Somalia and the impact on human nutrition and health.


Subject(s)
Drinking Water/chemistry , Goiter/epidemiology , Iodine/chemistry , Adolescent , Adult , Child , Cluster Analysis , Cross-Sectional Studies , Female , Food, Fortified , Humans , Iodine/administration & dosage , Iodine/urine , Male , Middle Aged , Nutrition Surveys , Nutritional Status , Prevalence , Sodium Chloride, Dietary/administration & dosage , Sodium Chloride, Dietary/urine , Somalia/epidemiology , Surveys and Questionnaires , Young Adult
5.
Med J Malaysia ; 69(5): 234-5, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25638240

ABSTRACT

Haemothorax is one of the less common presentations that requires hospital admission. Most cases are associated with underlying causes, but there is such an entity called spontaneous haemothorax. Spontaneous haemothorax is commonly associated with adhesions within the pleural cavity. Here, we reported two cases of young adults who presented with massive spontaneous haemothorax and required emergency thoracotomy for haemostasis purpose.

6.
J Environ Manage ; 129: 260-5, 2013 Nov 15.
Article in English | MEDLINE | ID: mdl-23968912

ABSTRACT

This study aims at developing a novel effluent removal management tool for septic sludge treatment plants (SSTP) using a clonal selection algorithm (CSA). The proposed CSA articulates the idea of utilizing an artificial immune system (AIS) to identify the behaviour of the SSTP, that is, using a sequence batch reactor (SBR) technology for treatment processes. The novelty of this study is the development of a predictive SSTP model for effluent discharge adopting the human immune system. Septic sludge from the individual septic tanks and package plants will be desuldged and treated in SSTP before discharging the wastewater into a waterway. The Borneo Island of Sarawak is selected as the case study. Currently, there are only two SSTPs in Sarawak, namely the Matang SSTP and the Sibu SSTP, and they are both using SBR technology. Monthly effluent discharges from 2007 to 2011 in the Matang SSTP are used in this study. Cross-validation is performed using data from the Sibu SSTP from April 2011 to July 2012. Both chemical oxygen demand (COD) and total suspended solids (TSS) in the effluent were analysed in this study. The model was validated and tested before forecasting the future effluent performance. The CSA-based SSTP model was simulated using MATLAB 7.10. The root mean square error (RMSE), mean absolute percentage error (MAPE), and correction coefficient (R) were used as performance indexes. In this study, it was found that the proposed prediction model was successful up to 84 months for the COD and 109 months for the TSS. In conclusion, the proposed CSA-based SSTP prediction model is indeed beneficial as an engineering tool to forecast the long-run performance of the SSTP and in turn, prevents infringement of future environmental balance in other towns in Sarawak.


Subject(s)
Environmental Monitoring/methods , Sewage/analysis , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/analysis , Algorithms , Biological Oxygen Demand Analysis , Bioreactors , Borneo , Malaysia , Models, Theoretical , Particulate Matter/analysis
7.
Food Nutr Bull ; 34(4): 420-8, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24605692

ABSTRACT

BACKGROUND: Stunting, acute malnutrition, and micronutrient malnutrition are persistent public health problems in refugee populations worldwide. In recent years there has been an increase in the availability and use of special nutritional products in emergency and development contexts to help address inadequate nutrient intakes from low-diversity diets. The availability of new special nutritional products, and the decision by the United Nations High Commissioner for Refugees (UNHCR) to use blanket supplementary feeding programs to prevent stunting and anemia, raised new challenges for designing, monitoring, and evaluating nutritional programs. OBJECTIVE: To develop an Operational Guidance on the use of special nutritional products for the prevention of micronutrient malnutrition, stunting, and acute malnutrition in refugee populations. Methods. A literature review and a series of consultations with technical experts, operational organizations, and field staff were performed over a period of 2 years. The Operational Guidance was finalized and released in December 2011. RESULTS: The Operational Guidance describes six stages for defining nutritionalproblems and identifying possible solutions; assessing and managing risks; testing acceptability and adherence, program design and implementation; and monitoring and evaluation. Key performance indicators are defined and a working nomenclature for new special nutritional products is described. CONCLUSIONS: The UNHCR Operational Guidance has filled an important gap in helping field staff deal with the opportunities and challenges of preventing undernutrition through the use of new products in blanket supplementary feeding programs. The need for further integration of guidance on selective feeding programs is discussed.


Subject(s)
Food Assistance , Malnutrition/prevention & control , Refugees , Africa , Asia , Child, Preschool , Food Assistance/organization & administration , Food, Fortified , Growth Disorders/prevention & control , Humans , Infant , Micronutrients/deficiency , Nutrition Policy , Nutritional Status , United Nations
8.
Community Dent Health ; 29(1): 33-8, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22482247

ABSTRACT

OBJECTIVE: To determine the associated factors of tooth wear (TW) among 16-year-old school children. METHOD AND MATERIALS: A random selection of secondary school children from 8 government secondary schools in Kota Bharu, Kelantan, Malaysia, participated in this case-control study. The Smith and Knight Tooth Wear Index and WHO criteria were used to chart tooth wear and dental caries respectively. Saliva analyses used standards recommended by GC Asia Dental. Self-administered questionnaire provided socio-demographic profile of the family, general knowledge of tooth wear, oral hygiene, food and drinks practices and other associated variables for tooth wear. Analysis using multiple logistic regression was performed. RESULTS: Of the 576 children sampled, 40% of the 460 controls were male as were 57% of the 116 in the case group. Multivariate analysis showed gender, monthly household income, carbonated drinks, caries experience, pool swimming, duration of intake of orange juice and hydration rate and viscosity were significantly associated with wear. CONCLUSION: The factors associated with tooth wear were similar to those encountered in other studies. Oral health promotion activities should emphasise those factors which can be changed. The erosive potential of some foods and drinks require further investigation.


Subject(s)
Tooth Wear/etiology , Adolescent , Beverages , Buffers , Carbonated Beverages , Case-Control Studies , Citrus sinensis , DMF Index , Drinking , Feeding Behavior , Female , Fruit , Humans , Hydrogen-Ion Concentration , Income , Malaysia , Male , Occupations , Oral Hygiene , Parents/education , Saliva/chemistry , Saliva/physiology , Secretory Rate/physiology , Sex Factors , Socioeconomic Factors , Swimming , Viscosity
9.
Matern Child Nutr ; 8(1): 49-56, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22250295

ABSTRACT

Iodine deficiency and excess are both associated with adverse health consequences, with fetuses, children and pregnant women being most vulnerable to the devastating effects of severe deficiency. It is often assumed that the iodine status of a population if displaced or in a remote or emergency situation is low. However, there is little evidence available to support this assumption, especially among long-term food-aid-dependent pregnant women. An effectiveness trial of a prenatal multiple-micronutrient supplement that contained 150 µg day(-1) iodine was conducted in two refugee camps in the North Eastern Province of Kenya in 2002. Urinary iodine concentration (UIC) was measured in a subsample of pregnant women attending antenatal care in Dagahaley (control camp) (n = 74) and Ifo (intervention camp) (n = 63). There was no significant difference in median UIC between the two camps (P = 0.118). The combined median UIC was 730 µg L(-1) (interquartile range, 780) (5.77 µmol L(-1)) and exceeded the upper safe limit of 500 µg L(-1) (3.95 µmol L(-1)) for pregnant women (P < 0.001), indicating excessive iodine intake. About 20% of the study subjects had 'more than adequate' urinary iodine, while over 71% had excessive UIC. Salt iodine content varied between 5.1 and 80.1 ppm in the five market salt samples analysed. In conclusion, excessive iodine intake was evident in the Dadaab refugee camps. Further research needs to be conducted to investigate the source of excess iodine, to determine the measures needed to address excessive iodine intake and to reconsider the World Health Organization/World Food Programme/United Nations Children's Fund guidance on supplementation of vulnerable groups in emergencies.


Subject(s)
Iodine/administration & dosage , Iodine/adverse effects , Maternal Nutritional Physiological Phenomena/physiology , Refugees , Sodium Chloride, Dietary/administration & dosage , Diet Surveys , Dose-Response Relationship, Drug , Female , Food, Fortified , Humans , Iodine/chemistry , Iodine/deficiency , Iodine/urine , Nutritional Requirements , Pregnancy , Pregnancy Complications , Refugees/statistics & numerical data , Somalia , Young Adult
10.
Ecotoxicol Environ Saf ; 72(2): 496-506, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18243309

ABSTRACT

The distributions of Cu, Zn, and Pb concentrations in the selected soft tissues (foot, cephalic tentacle, mantle, muscle, gill, digestive caecum, and remaining soft tissues) and shells of the mud-flat snail Telescopium telescopium were determined in snails from eight geographical sites in the south-western intertidal area of Peninsular Malaysia. Generally, the digestive caecum compared with other selected soft tissues, accumulated higher concentration of Zn (214.35+/-14.56 microg/g dry weight), indicating that the digestive caecum has higher affinity for the essential Zn to bind to metallothionein. The shell demonstrated higher concentrations of Pb (41.23+/-1.20 microg/g dry weight) when compared to the selected soft tissues except gill from Kuala Sg. Ayam (95.76+/-5.32 microg/g dry weight). The use of different soft tissues also can solve the problem of defecation to reduce error in interpreting the bioavailability of heavy metals in the intertidal area.


Subject(s)
Copper/toxicity , Environmental Monitoring/methods , Gastropoda/drug effects , Lead/toxicity , Soil Pollutants/toxicity , Water Pollutants, Chemical/toxicity , Zinc/toxicity , Animals , Copper/pharmacokinetics , Gastropoda/metabolism , Industrial Waste , Lead/pharmacokinetics , Malaysia , Metallothionein/metabolism , Seawater , Soil Pollutants/pharmacokinetics , Tissue Distribution , Water Pollutants, Chemical/pharmacokinetics , Zinc/pharmacokinetics
11.
Public Health Nutr ; 11(7): 720-8, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18096105

ABSTRACT

OBJECTIVE: To assess changes in the Fe and vitamin A status of the population of Nangweshi refugee camp associated with the introduction of maize meal fortification. DESIGN: Pre- and post-intervention study using a longitudinal cohort. SETTING: Nangweshi refugee camp, Zambia. SUBJECTS: Two hundred and twelve adolescents (10-19 years), 157 children (6-59 months) and 118 women (20-49 years) were selected at random by household survey in July 2003 and followed up after 12 months. RESULTS: Maize grain was milled and fortified in two custom-designed mills installed at a central location in the camp and a daily ration of 400 g per person was distributed twice monthly to households as part of the routine food aid ration. During the intervention period mean Hb increased in children (0.87 g/dl; P < 0.001) and adolescents (0.24 g/dl; P = 0.043) but did not increase in women. Anaemia decreased in children by 23.4% (P < 0.001) but there was no significant change in adolescents or women. Serum transferrin receptor (log10-transformed) decreased by -0.082 microg/ml (P = 0.036) indicating an improvement in the Fe status of adolescents but there was no significant decrease in the prevalence of deficiency (-8.5%; P = 0.079). In adolescents, serum retinol increased by 0.16 micromol/l (P < 0.001) and vitamin A deficiency decreased by 26.1% (P < 0.001). CONCLUSIONS: The introduction of fortified maize meal led to a decrease in anaemia in children and a decrease in vitamin A deficiency in adolescents. Centralised, camp-level milling and fortification of maize meal is a feasible and pertinent intervention in food aid operations.


Subject(s)
Anemia, Iron-Deficiency/therapy , Food, Fortified , Hemoglobins/analysis , Iron/administration & dosage , Vitamin A Deficiency/therapy , Vitamin A/administration & dosage , Adolescent , Adult , Anemia, Iron-Deficiency/blood , Anemia, Iron-Deficiency/epidemiology , Child , Child, Preschool , Cohort Studies , Female , Humans , Infant , Iron/blood , Longitudinal Studies , Male , Nutritional Requirements , Nutritional Status , Nutritive Value , Public Health , Refugees , Treatment Outcome , United Nations , Vitamin A/blood , Vitamin A Deficiency/blood , Vitamin A Deficiency/epidemiology , Zambia , Zea mays/chemistry
15.
Eur J Ophthalmol ; 16(4): 509-13, 2006.
Article in English | MEDLINE | ID: mdl-16952086

ABSTRACT

PURPOSE: To establish the efficacy of a regional nerve block of the upper eyelid and its effect on levator motor function. METHODS: Forty-one patients underwent surgery on 54 upper eyelids by one surgeon, after administration of a regional nerve block at the supraorbital notch. The amount of pain experienced by patients due to the local anesthetic injection and surgery was determined by using visual analogue scores. The effect of the local anesthetic injection on levator function was determined by comparing the measured levator function prior to and following administration. Any complications attributable to the regional sensory nerve block were recorded. RESULTS: Ninety-two percent of patients found the injection painless, and the rest reported negligible pain. The mean pain score for the injection was 2 (SD 1.3, range 0-6). The mean pain score for the surgery was 0.3 (SD 0.6, range 0-3). No significant difference was found in levator function prior to and following the injection (pre-function: 14.4 mm, post-function: 13.4 mm, p=0.01). One patient had hematoma formation at the site of injection. CONCLUSIONS: A regional nerve block of the upper eyelid achieves effective sensory anesthesia,without compromising motor function. This helps in an accurate assessment of intraoperative height during upper lid surgery.


Subject(s)
Blepharoplasty/methods , Blepharoptosis/surgery , Eyelids/innervation , Nerve Block/methods , Oculomotor Muscles/innervation , Ophthalmic Nerve/physiology , Adult , Aged , Aged, 80 and over , Anesthesia, Local/methods , Anesthetics, Local , Epinephrine , Female , Humans , Lidocaine , Male , Middle Aged , Oculomotor Muscles/physiology , Pain Measurement , Pain, Postoperative
16.
Eur J Ophthalmol ; 16(1): 153-60, 2006.
Article in English | MEDLINE | ID: mdl-16496261

ABSTRACT

PURPOSE: To describe the cataract morphology and genetic and biochemical findings in a four-generation family with hereditary hyperferritinemia cataract syndrome (HHCS). METHODS: Family members of the proband with HHCS were investigated. DNA sequencing was carried out to identify the iron responsive element (IRE) of the L-ferritin gene in affected and non-affected family members. Molecular modeling allowed prediction of the structure of the mutant IRE in affected cases. Serum ferritin and transferrin saturation were determined using standard methods. All family members underwent slit lamp examination by an ophthalmologist to document presence of cataract or lens status. Cataract morphology was documented where present. RESULTS: This family with HHCS had the genetic heterozygous mutation G32C in the IRE of the L-ferritin mRNA. Lens opacities were detectable in young members of the family, and morphology of cataracts was consistent with previous reports. Biochemical testing demonstrated high serum ferritin levels in affected individuals. CONCLUSIONS: The morphology of cataracts in HHCS seems to be similar in all cases. In the heterozygous G32C mutation, the age at onset of cataracts is very early. Greater awareness of this condition among ophthalmologists will lead to effective family counseling of those affected, by genetic testing or simple biochemical tests. Serum ferritin levels can be effectively used to screen for this condition in suspected families.


Subject(s)
Cataract/genetics , Eye Diseases, Hereditary , Ferritins/blood , Iron Metabolism Disorders/genetics , Iron-Regulatory Proteins/genetics , Adolescent , Adult , Cataract/blood , Cataract/pathology , Child, Preschool , DNA Mutational Analysis , Female , Humans , Infant , Iron Metabolism Disorders/blood , Iron Metabolism Disorders/pathology , Middle Aged , Mutation , Pedigree , RNA, Messenger/genetics , Syndrome
18.
Med J Malaysia ; 55(4): 498-505, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11221164

ABSTRACT

Despite advancements in endoscopy and pharmacology in the treatment of peptic ulcer disease the overall mortality has remained constant at 10% for the past four decades. The aim of this study was to determine the age, gender, racial distribution, incidence and causes of endoscopically diagnosed cases of upper gastrointestinal (UGI) bleeding to summarise treatments undertaken and to report their outcome. A prospective study of UGI bleeding in 128 patients was performed in two surgical wards of Kuala Lumpur Hospital, involving both elective and emergency admissions. The study group comprised of 113 (88.2%) males and 15 (11.7%) females. The mean age was 51.9 years (range 14 to 85 years) and 37.5% (48 of 128 patients) were older than 60 years. The Indian race was over-represented in all disease categories. Smoking (50.1%), alcohol consumption (37.5%), non-steroidal anti-inflammatory drugs (NSAIDs) (17.2%), traditional remedies (5.5%), anti-coagulants (2.3%) and steroids (0.8%) were among the risk factors reported. Common presenting symptoms and signs included malaena (68.8%), haematemesis (59.4%) and fresh per rectal bleeding (33.6%). The commonest causes of UGI bleeding were duodenal ulcer (32%), gastric ulcer (29.7%), erosions (duodenal and gastric) (21.9%), oesophageal varices (10.9%) and malignancy (3.9%). UGI bleeding was treated non-surgically in 90.6% of cases. Blood transfusions were required in 62.6% (67/107) of peptic ulcer disease patients. Surgical intervention for bleeding peptic ulcer occurred in around 10% of cases and involved under-running of the bleeding vessel in most high risk duodenal and gastric ulcer patients. The overall mortality from bleeding peptic ulcer disease was 4.7%. Six patients died from torrential UGI haemorrhage soon after presentation, without the establishment of a cause. Active resuscitative protocols, early endoscopy, more aggressive interventional therapy, early surgery by more senior surgeons, increasing intensive care unit beds and more active participation of multidisciplinary teams in co-ordinating management are among remedial measures advocated. Broader educational preventive strategies should target the causes of UGI bleeding.


Subject(s)
Gastrointestinal Hemorrhage/epidemiology , Gastrointestinal Hemorrhage/therapy , Hospitals , Adolescent , Adult , Aged , Aged, 80 and over , Female , Gastrointestinal Hemorrhage/etiology , Gastrointestinal Hemorrhage/mortality , Humans , Incidence , Malaysia/epidemiology , Male , Middle Aged , Risk Factors
19.
J Biomech ; 32(3): 317-21, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10093032

ABSTRACT

Motion analysis systems typically introduce noise to the displacement data recorded. Butterworth digital filters have been used to smooth the displacement data in order to obtain smoothed velocities and accelerations. However, this technique does not yield satisfactory results, especially when dealing with complex kinematic motions that occupy the low- and high-frequency bands. The use of the discrete wavelet transform, as an alternative to digital filters, is presented in this paper. The transform passes the original signal through two complementary low- and high-pass FIR filters and decomposes the signal into an approximation function and a detail function. Further decomposition of the signal results in transforming the signal into a hierarchy set of orthogonal approximation and detail functions. A reverse process is employed to perfectly reconstruct the signal (inverse transform) back from its approximation and detail functions. The discrete wavelet transform was applied to the displacement data recorded by Pezzack et al., 1977. The smoothed displacement data were twice differentiated and compared to Pezzack et al.'s acceleration data in order to choose the most appropriate filter coefficients and decomposition level on the basis of maximizing the percentage of retained energy (PRE) and minimizing the root mean square error (RMSE). Daubechies wavelet of the fourth order (Db4) at the second decomposition level showed better results than both the biorthogonal and Coiflet wavelets (PRE = 97.5%, RMSE = 4.7 rad s-2). The Db4 wavelet was then used to compress complex displacement data obtained from a noisy mathematically generated function. Results clearly indicate superiority of this new smoothing approach over traditional filters.


Subject(s)
Biomechanical Phenomena , Mathematical Computing , Algorithms
20.
An Med Interna ; 7(7): 361-3, 1990 Jul.
Article in Spanish | MEDLINE | ID: mdl-2103249

ABSTRACT

Mesenteric venous thrombosis is a rare disease, and is secondary to several known causes. Recently, it has been proven that some coagulation alterations (such as: antithrombin III deficit, plasminogen, S protein, etc.) play a role in its pathogenesis. Nevertheless, 10% of the cases are still of unknown origin (primary mesenteric venous thrombosis). We present a case of primary mesenteric venous thrombosis with a very good clinical evolution.


Subject(s)
Mesenteric Vascular Occlusion/diagnosis , Thrombosis/diagnosis , Adult , Emergencies , Female , Humans , Infarction/surgery , Jejunum/blood supply , Jejunum/surgery , Mesenteric Vascular Occlusion/surgery , Mesenteric Veins , Thrombosis/surgery
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