11 research outputs found
A Study of Hybrid Solar Air Conditioning
In this progress report, it addresses several researches on the hybrid solar air
conditioner with its critical component and mechanism. Some calculation has been made to
determine the betterment of the proposed system of the solar air conditioner. Nowadays, the
necessity of having air conditioner at our home was highly demand at home and in public
areas due to the large demand for comfort in the thermal environment of living space in
modern society. Since the demand of the air conditioner had increase from year to year and
the air conditioner had consumed big amount of electricity to operate, a new system of air
conditioner has been discovered and developed which is by adding solar energy.
Air-conditioner consumes almost 50% of the primary energy supplied to a building.
The cooler the temperature, the bigger the energy or electricity needed to run the airconditioner.
60 % of the power consumed by the air conditioner is used by the compressor
whereas the other 40% is used to operate other components in air conditioning. Therefore, by
decreasing the consumption of electricity by the compressor may decrease the power
consumption of an air-conditioner.
This report discusses a new system of air-conditioning to decrease the power
consumption that uses the heat energy from the solar collector to support and enhance the
heating of refrigerant, thus decrease the work load of the compressor. It focuses on the new
system of the air conditioner which is a solar collector, added after the compressor in the air
conditioner cycle. The collector used for the experimentations is discussed and evacuated
tube solar collector is selected and the refrigerant used is R407. The project showing that the
propose design can reduce the power consumption by the air conditioner by about 30% lower
than conventional air conditioner
Diagnostic Cerebral Angiography in Spontaneous Intracranial Haemorrhage: A Guide for Developing Countries
ObjectiveSpontaneous intracranial haemorrhage constitutes 18-40% of all stroke cases. Indications for cerebral angiography to find underlying potentially treatable vascular abnormalities are not clear. This study determined which intracranial haemorrhage patients need cerebral angiography by correlating computed tomography (CT) findings, age and hypertension history with cerebral angiography findings.MethodsA total of 54 patients (8-79 years) with intracranial haemorrhage who underwent both CT examination and six-vessel cerebral angiography were studied over a 2-year period. Cerebral angiography was repeated within 6 weeks if the first angiogram was negative.ResultsAngiography detected vascular lesions in 50% of cases (aneurysm 38.9% and arteriovenous malformation, AVM, 11.1%). In the aneurysm group, angiographic yield was 34.3% whereas in the AVM group, it was 37.9%. Subarachnoid haemorrhage (SAH) combined with other types of haemorrhage (such as intracerebral haemorrhage, ICH) was not significantly correlated with the likelihood of finding a vascular lesion, both aneurysm and AVM (p = 0.157). Age less than 50 years had significant correlation (p = 0.021) in the AVM group as well as in the aneurysm group (p < 0.001). A history of hypertension was associated with both aneurysm (p = 0.039) and AVM (p = 0.008). No patients with deep intracerebral haematoma had vascular lesions. The presence of an intraventricular haemorrhage (IVH) had significant correlation with aneurysm (p = 0.008) but not AVM. There was no significant difference in mean age between patients with and without a vascular lesion (p = 0.134).ConclusionCerebral angiography is justified in patients with pure SAH (p = 0.001). Other factors associated with finding a vascular lesion were a history of hypertension and the presence of IVH. Diagnostic cerebral angiography is indicated for patients with ICH and SAH and IVH with a history of hypertension, regardless of age
Homology modeling and docking studies of δ19-fatty acid desaturase from a Cold-tolerant Pseudomonas sp. AMS8
Membrane-bound fatty acid desaturases perform oxygenated desaturation reactions to insert double bonds within fatty acyl chains in regioselective and stereoselective manners. The Δ9-fatty acid desaturase strictly creates the first double bond between C9 and 10 positions of most saturated substrates. As the three-dimensional structures of the bacterial membrane fatty acid desaturases are not available, relevant information about the enzymes are derived from their amino acid sequences, site-directed mutagenesis and domain swapping in similar membrane-bound desaturases. The cold-tolerant Pseudomonas sp. AMS8 was found to produce high amount of monounsaturated fatty acids at low temperature. Subsequently, an active Δ9-fatty acid desaturase was isolated and functionally expressed in Escherichia coli. In this paper we report homology modeling and docking studies of a Δ9-fatty acid desaturase from a Cold-tolerant Pseudomonas sp. AMS8 for the first time to the best of our knowledge. Three dimensional structure of the enzyme was built using MODELLER version 9.18 using a suitable template. The protein model contained the three conserved-histidine residues typical for all membrane-bound desaturase catalytic activity. The structure was subjected to energy minimization and checked for correctness using Ramachandran plots and ERRAT, which showed a good quality model of 91.6 and 65.0%, respectively. The protein model was used to preform MD simulation and docking of palmitic acid using CHARMM36 force field in GROMACS Version 5 and Autodock tool Version 4.2, respectively. The docking simulation with the lowest binding energy, −6.8 kcal/mol had a number of residues in close contact with the docked palmitic acid namely, Ile26, Tyr95, Val179, Gly180, Pro64, Glu203, His34, His206, His71, Arg182, Thr85, Lys98 and His177. Interestingly, among the binding residues are His34, His71 and His206 from the first, second, and third conserved histidine motif, respectively, which constitute the active site of the enzyme. The results obtained are in compliance with the in vivo activity of the Δ9-fatty acid desaturase on the membrane phospholipids
Diagnostic Cerebral Angiography in Spontaneous Intracranial Haemorrhage: A Guide for Developing Countries
Spontaneous intracranial haemorrhage constitutes 18-40% of all stroke cases. Indications for cerebral angiography to find underlying potentially treatable vascular abnormalities are not clear. This study determined which intracranial haemorrhage patients need cerebral angiography by correlating computed tomography (CT) findings, age and hypertension history with cerebral angiography findings.
Methods: A total of 54 patients (8-79 years) with intracranial haemorrhage who underwent both CT examination and six-vessel cerebral angiography were studied over a 2-year period. Cerebral angiography was repeated within 6 weeks if the first angiogram was negative.
Results: Angiography detected vascular lesions in 50% of cases (aneurysm 38.9% and arteriovenous malformation, AVM, 11.1%). In the aneurysm group, angiographic yield was 34.3% whereas in the AVM group, it was 37.9%. Subarachnoid haemorrhage (SAH) combined with other types of haemorrhage (such as intracerebral haemorrhage, ICH) was not significantly correlated with the likelihood of finding a vascular lesion, both aneurysm and AVM (p = 0.157). Age less than 50 years had significant correlation (p = 0.021) in the AVM group as well as in the aneurysm group (p < 0.001). A history of hypertension was associated with both aneurysm (p = 0.039) and AVM (p = 0.008). No patients with deep intracerebral haematoma had vascular lesions. The presence of an intraventricular haemorrhage (IVH) had significant correlation with aneurysm (p = 0.008) but not AVM. There was no significant difference in mean age between patients with and without a vascular lesion (p = 0.134).
Conclusion: Cerebral angiography is justified in patients with pure SAH (p = 0.001). Other factors associated with finding a vascular lesion were a history of hypertension and the presence of IVH. Diagnostic cerebral angiography is indicated for patients with ICH and SAH and IVH with a history of hypertension, regardless of age
Enhancing sustainability performance by cleaner production value stream mapping at soybean curd process
Development of an aquaponic system using ablution greywater for recreational purpose
The ablution ritual consumes large quantities of water, especially in mosques and public prayer rooms, where the greywater is allowed to run free and drain away. In Malaysia, most ablution system consists of a line of water taps with a drainage trough to carry the greywater to main drains. Some decent water is lost in the process as the tap is left running. In view of unnecessary waste, a simple recycling system can be designed to collect, treat and reuse the ablution water within a close-loop system for non-drinking applications, such as toilet flushing, general washing, plants watering and flowerbed cultivation. Therefore, this study was conducted to recover and reuse the ablution greywater that produced from Masjid Sultan Ibrahim with an aquaponic system. The aquaponic system involves the use of fish as a source of nutrients for the plant's growth, while the plants filter the water for the fish. In addition, the aquatic system model has its own attraction value that is very compatible with the landscape of the Masjid Sultan Ibrahim and at the same time it also provides recreational activities
Diagnostic Cerebral Angiography in Spontaneous Intracranial Haemorrhage: A Guide for Developing Countries
Expression of GBS virulence genes in high vaginal swabs of symptomatic pregnant women at Hospital Tengku Ampuan Afzan, Kuantan
During pregnancy, group B streptococcus (GBS) colonization is known as one of the risk factors for preterm birth and consequently neonatal infections. Previous in-vitro experiments using human cells and in vivo animal models have portrayed the important roles of these virulence factors including hemolytic pigment (CylE), hyaluronidase (HylB), serine-rich protein (Srr) and bacterial surface adhesion of GBS (BsaB) in mediating GBS colonization and intrauterine ascending infection, leading to preterm delivery. The aim of this study is to investigate the association between mRNA expression of women and preterm delivery. GBS isolates were obtained from high vaginal swabs of pregnant women(n=40) with gestational age less than 37 weeks and symptoms including preterm labour, preterm premature rupture of membrane (pPROM), vaginal discharge and vaginal bleeding. Socio-demographic details, obstetric history and delivery outcomes of these women were also enquired. RNA was extracted from these GBS isolates and RT-qPCR was performed to determine the relative mRNA expression of GBS virulence genes including CylE,HylB, Srr and BsaB. Socio-demographic details and obstetric history were not found to be associated with the delivery outcomes of these women. Women with preterm labour and pPROM who delivered prematurely were demonstrated with higher expression of HylB and Cyl Egenes, in comparison to women with term delivery. The expression of Srr and BsaB genes were both similar between symptomatic pregnant women who had term and preterm delivery. Theseresultssuggestthatfollowingvaginalcolonization,bothCylEandHylBgenespossiblycontributetointrauterineascendinginfectionandinflammation,leading to preterm delivery in humans.Thus, hemolytic pigment and hyaluronidase may be targeted for exploratory and pre-clinical stages of vaccine development, which is a good alternative to intrapartum antibiotic prophylaxis in order to prevent neonatal GBS infections