Insecticide resistance in malaria vectors in central Sudan

Malaria is the leading cause of mortality and morbidity in Sudan. The annual malaria cases and deaths are estimated at 7.5 million and 35, 000 respectively. One of the possible factors that have led to this situation is the development of insecticide resistance in the main malaria vector in Sudan, Anopheles arabiensis. This study therefore, was initiated to identify the malaria vectors in Gezira and Sennar states of central Sudan, determine their susceptibility levels to the different classes of insecticides used for malaria vector control, identify mechanisms of resistance, and determine the sporozoite infection rate and the blood meal sources in these populations. The polymerase chain reaction (PCR) for species identification revealed that An. arabiensis was the only member of the An. gambiae complex present in the study area. The blood meal analysis using ELISA showed high anthropophily with 89.2% feeding on humans. The overall sporozoite infection rate was 2.3 %. WHO susceptibility tests showed complete susceptibility of An. arabiensis to bendiocarb (100% mortality) and multiple resistance to permethrin (54-78%), DDT (55-66%) and malathion (76-78%). The kdr mutation analysis revealed the presence of the West African kdr allele with the majority of specimens being heterozygous (RS). The kdr in DDT/permethrin susceptible specimens were: 15% homozygous for the kdr mutation (RR), 64.2% heterozygous (RS) and 20.8% homozygous for the susceptible allele (SS). Amongst the DDT/permethrin resistant specimens, 13% were SS, 48.7% RS and 38.3% RR. The apparent lack of correlation between kdr and resistant phenotype strongly suggests that other resistance mechanisms are playing a role

WLAN Integrated with GPRS Network Securely

In this paper a WLAN network that accesses the Internet through a GPRS network was implemented and tested. The proposed network is managed by the Linux based server. Because of the limited facilities of GPRS such as dynamic IP addressing besides to its limited bandwidth a number of techniques are implemented to overcome these limitations.Dynamic Host Configuration Protocol (DHCP) server was added to provide a single central control for all TCP/IP resources. Squid Proxy was added to provide caching of the redundant accessed Web content to reduce the Internet bandwidth usage and speeding up the clients download time. Network Address Translation (NAT) service was configured to share one IP address among several different systems. In order to accomplish a secure channel to exchange data between two network devices, the Secure Shell (SSH) protocol was added. The first test shows that the data transfer rate at different time intervals of the day found to be an average of 10.95 Kbps for uploading and 13.7 Kbps for downloading and the second test shows that the network performance improved when squid proxy cache was used. The data rate found to be 143.3 Kbps average for uploading rate and 376.6 Kbps average for downloading rate

Channel Estimation and Prediction Based Adaptive Wireless Communication Systems

Wireless channels are typically much more noisy than wired links and subjected to fading due to multipath propagation which result in ISI and hence high error rate. Adaptive modulation is a powerful technique to improve the tradeoff between spectral efficiency and Bit Error Rate (BER). In order to adjust the transmission rate, channel state information (CSI) is required at the transmitter side.In this paper the performance enhancement of using linear prediction along with channel estimation to track the channel variations and adaptive modulation were examined. The simulation results shows that the channel estimation is sufficient for low Doppler frequency shifts (<30 Hz), while channel prediction is much more suited at high Doppler shifts with same SNR and target BER=10-4. It was shown that the performance at higher Doppler frequency shifts (<30Hz) was improved by more than 2dB over channel estimation at target BER=10-4 and 32QAM constellation used

Case of escape in cassava, Manihot esculenta Crantz

Two cassava escapes where collected from cultivated fields near natural habitat in Bolivia. They are described morphologically and analyzed cytogenetically in this study. It is suggested that they are the product of backcrosses of cassava interspecific hybrids with the cultigen itself, and that selective conditions have developed in which certain forms of cassava segregates have adapted to grow wildly in natural habitats near cassava fields. These segregates may hybridize with cultivated cassava upon coming in contact with such varieties. Because these escapes have incorporated useful genes from the wild into their genetic structure, they could be used for cassava improvement since their genetic barriers with other forms of cassava are very weak

Dokaz američke serološke skupine orbivirusa upotrebom višestruke RT-PCR.

A multiplex RT-PCR assay, for simultaneous detection and differentiation of United States serogroup of Orbiviruses, including bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) in cell culture, was developed. Sets of primers were designed to hybridize to genome segment six of EHDV-2 and to genome segment 10 of BTV-10. The RT-PCR assay utilized a single-tube PCR amplification in which EHDV and BTV primers were used simultaneously in a multiplex format. The EHDV primers produced a 387 base pair (bp) specific PCR product from RNA samples of cell culture-adapted EHDV serotypes 1 and 2, but not from BTV serotypes 2, 10, 11, 13, 17; or from total nucleic acid extract of baby hamster kidney (BHK) cells controls. Likewise, the BTV primers generated a 251-bp amplicon from RNA samples of BTV serotypes 2, 10, 11, 13, and 17, whereas EHDV-1 and EHDV-2; and BHK- 21 cells total nucleic acid extract failed to demonstrate the 251-bp specific BTV PCR product. EHDV and BTV PCR amplification products were easily identified on the basis of size differences on ethidium bromide stained agarose gels. This multiplex RT-PCR assay provides supportive diagnostic method for rapid detection of BTV and/or EHDV infections among susceptible ruminants.Rabljen je višestruki RT-PCR (lančana reakcija polimerazom uz prethodnu reverznu transkripciju) za dokazivanje i razlikovanje serološke skupine virusa bolesti plavog jezika (BPJ) i virus epizootske hemoragijske bolesti jelena (EHB) izdvojenih u SAD-u te uzgojenih na staničnoj kulturi. Određeni su parovi početnica za hibridizaciju na odsječak 6 genoma virusa EHB-2 te na odsječak 10 genoma virusa BPJ-10. Za RT-PCR korištena je PCR amplifikacija u jednoj epruveti u kojoj su početnice za virus EHB i virus BPJ istodobno upotrijebljene u višestrukom obliku. Pomoću početnica virusa EHB proizvedeno je 387 parova baza (pb) specifičnog proizvoda PCR iz uzoraka RNA serotipova 1 i 2 toga virusa prilagođenog na staničnu kulturu, ali ne i iz serotipova 2, 10, 11, 13 i 17 virusa BPJ ili iz ekstrakta ukupne nukleinske kiseline kontrolne stanične kulture bubrega hrčka (BHK). Početnice za virus BPJ dovele su do proizvoda od 251 para baza iz uzoraka RNA serotipova 2, 10, 11, 13 i 17 toga virusa, dok serotipovi 1 i 2 virusa EHB i ukupni ekstrakt nukleinske kiseline stanične kulture BHK-21 nisu doveli do specifičnog proizvoda od 251 para baza. Umnoženi proizvodi PCR za viruse EBH i BPJ mogli su se jednostavno identificirati na osnovi razlika u veličini na agaroznom gelu obojenom etidij-bromidom. Postupak višestruke RT-PCR pruža pomoćnu dijagnostičku metodu za brzo dokazivanje infekcija uzrokovanih virusima BPJ i EHB među prijemljivim preživačima

An Abdominal Aortic Aneurysm, Intramural Thrombus and Moderate Leak in an Asian Man Presenting with Acute Gastroenteritis

Introduction: Missing a leaking abdominal aortic aneurysm (AAA) is common in medical practice because few at-risk patients have a history of AAA and many have an unusual presentation. Background: AAA is less common among Asians than white Caucasians of the same age. Our patient had no significant risk factors apart from age and sex and had an unusual presentation. Patient and Methods: A 67-year-old Asian man presented to the emergency room (ER) with a 1-day history of nausea, vomiting, diarrhoea, fever and abdominal pain. He was febrile, dehydrated. and had marked tenderness at the right iliac fossa. Laboratory findings suggested bacterial gastroenteritis but this did not explain the localized tenderness at the right iliac fossa. Result and Discussion: A CT scan of the abdomen revealed an AAA arising above the origins of the renal arteries, an intramural thrombus, a retroperitoneal haematoma and a leak extending to the right iliac fossa. The patient was transferred to another hospital and underwent exploratory laparotomy, surgical repair of the aneurysm, and aortobi-iliac grafting with removal of the thrombus. The patient was discharged in good shape 3 weeks after surgery. Without the CT scan of the abdomen, the AAA could have been missed and the patient treated for severe gastroenteriti

Environmental knowledge and city perception: with a focus on the energy link to environmental aesthetics

Architecture exists to respond to environmental problems that affect human life, many of which are directly related to energy principles. In the early stages of man's adaptation, these challenges set the criteria for indigenous architecture. Certain formal solutions became recognised as more reliable in meeting environmental potentials and a deep appreciation of these emerged. This persisted even as the evolution of the intellect allowed man to move away from direct, survivalist responses to the environment into a more symbol -based and mutual relationship.The process of change, however, has developed into one of internationalisation. In Libya, the subject area of this thesis, building techniques are used that have no relevance to the environment. This fracture between the natural and artificial has created many problems. This thesis will research these accumulated problems by studying the city image, which lead the author to assert the role of energy in setting the criteria for environmental quality

Valorization of Bambara groundnut shell via intermediate pyrolysis: Products distribution and characterization

This study provides first report on thermochemical conversion of residue from one of the underutilized crops, Bambara groundnut. Shells from two Bambara groundnut landraces KARO and EX-SOKOTO were used. Pyrolysis was conducted in a vertical fixed bed reactor at 500, 550, 600 and 650 o�C; 50 o�C/min heating rate and 5 L/min nitrogen flow rate. The report gives experimental results on characteristic of the feedstock, impact of temperature on the pyrolysis product distribution (bio-oil, bio-char and noncondensable gas). It evaluates the chemical and physicochemical properties of bio-oil, characteristics of bio-char and composition of the non-condensable gas using standard analytical techniques. KARO shell produced more bio-oil and was maximum at 600 o�C (37.21 wt%) compared to EX-SOKOTO with the highest bio-oil yield of 32.79 wt% under the same condition. Two-phase bio-oil (organic and aqueous) was collected and analyzed. The organic phase from both feedstocks was made up of benzene derivatives which can be used as a precursor for quality biofuel production while the aqueous from KARO consisted sugars and other valuable chemicals compared to the aqueous phase from EX-SOKOTO which comprised of acids, ketones, aldehydes and phenols. Characteristics of bio-char and composition of the noncondensable were also determined. The results show that bio-char is rich in carbon and some minerals which can be utilized either as a solid fuel or source of bio-fertilizer. The non-condensable gas was made up of methane, hydrogen, carbon monoxide and carbon dioxide, which can be recycled to the reactor as a carrier gas. This study demonstrated recovery of high quality fuel precursor and other valuable materials from Bambara groundnut shell

Traditional Underground Grain Storage in Clay Soils in Sudan Improved by Recent Innovations

In the central clay plain of the Sudan, traditional subsistence farmers and small farmers that also produce for local markets want to keep the region near food self-sufficiency. They combine annual production of sorghum with underground pit storage of part of the harvest. With increasing climate variability this food security is coming more and more under pressure. Farmers recently experimented with pit innovations that would allow storage for more than one season. These innovations were quantified and further improvements were suggested. It was found that in the most abundantly occurring cracking clay soils, wide shallow pits, using thick chaff linings, with wider above ground soil caps, are most suitable for longer term storage