On sparse representations of linear operators and the approximation of matrix products

Thus far, sparse representations have been exploited largely in the context of robustly estimating functions in a noisy environment from a few measurements. In this context, the existence of a basis in which the signal class under consideration is sparse is used to decrease the number of necessary measurements while controlling the approximation error. In this paper, we instead focus on applications in numerical analysis, by way of sparse representations of linear operators with the objective of minimizing the number of operations needed to perform basic operations (here, multiplication) on these operators. We represent a linear operator by a sum of rank-one operators, and show how a sparse representation that guarantees a low approximation error for the product can be obtained from analyzing an induced quadratic form. This construction in turn yields new algorithms for computing approximate matrix products.Comment: 6 pages, 3 figures; presented at the 42nd Annual Conference on Information Sciences and Systems (CISS 2008

Optimization of growth and extracellular glucoamylase production by Candida famata isolate

Candida famata was isolated from traditional Moroccan sourdough. It exhibited high glucoamylase and biomass production. Starch induces high glucoamylase production C. famata with maximum glucoamylase activity at 5 g/L. Glucose stimulates good production in biomass but strongly inhibitsglucoamylase production. Among the sources of nitrogen tested, yeast extract and the (NH4)2HPO4 gave maximum glucoamylase and biomass after 72 h of incubation in liquid medium at 30°C, pH 5 and 105 rpm

Low dose unfractionated heparin with low dose aspirin in treatment of thrombo prophylaxis in utero placental insufficiency: a new vision in heparinization during pregnancy

Background: The use of heparin and aspirin in obstetric care has grown considerably since their introduction into clinical practice. Because of the physiological changes of pregnancy, the usage of heparin and optimal dosage of heparin remains uncertain. Here our institute designed low dose Unfractionated Heparin (5000 IU s/c daily) as thrombo Prophylaxis regimen. To study the outcome of low dose UFH (5000 IU sc /daily) + Low dose aspirin (75 mg oral per day) for thrombo prophylaxis in utero placental insufficiency, in patient with 2 or more abortions.Methods: This retrospective study was conducted in 135 patients with 2 or more abortions as obstetric history. Prophylactic low dose of UFH (5000 IU s/c daily) + LDA 75 mg oral was initiated.  The Primary outcome is live birth, and secondary outcomes is Reduced incidence of early onset of gestational hypertension (HT), Intrauterine Growth Retardation (IUGR).Results: Out of 135 women 131 gave live birth, 2 had first trimester abortion and 2 had intrauterine death by 5 to 6 months. PIH was higher in patients with more than 30 years of age.Conclusions: In our Retrospective, data combination of low dose UFH (5000IU s/c) + LDA (75mg oral) is as safe as routine thrombo prophylaxis with good compliance

Performance of a local signalized intersection for handling traffic operation in Baghdad City

The inspection of the flexibility and performance of a local signalized intersection in managing traffic operation in Baghdad city is the main target of this study. Andalus intersection is one of the important local intersections in Bagdad city which recorded remarkable traffic congestion problem now a days and have been chosen in this study as a part of continuous studies due to its vital location. Smart Traffic Analysis (STA) software is used to give an aspect to the inefficient performance of the Andalus signalized intersection having three approached links and four exit legs while SYNCHRO software is used to simulate the data analysis and offer different alternative solutions to solve the congestion problem. From the obtained data analysis it has been found that the best suggested alteration for handling the current traffic volume of each studied intersection approach is the signalized intersection with optimum cycle time combined with the addition of two lanes, where the mean delay for the entire intersection can be reduced by approximately 26% by applying alteration No.1 while the mean delay for the entire intersection can be reduce approximately by 31% by applying alteration No.2. Furthermore, the queue length for the entire intersection can be reducing by approximately 6% and 17% for alteration No.1 and No.2 respectively

Rain Water Characterization at Urban and Rural (North B) Unguja

Aim of the study was to assess the physicochemical characteristics of rainwater at urban and rural (north B) Unguja. Twenty four (24) rainwater samples were analyzed for pH, electrical conductivity (EC) and total dissolved solids (TDS) and cations: calcium (Ca2+), copper (Cu2+), iron (Fe2+), chromium (Cr VI) , and anions: fluoride (F-), nitrite and sulfate (SO42-). The investigated physicochemical parameters in the rainwater samples were within the permissible limits of the World Health Organization (WHO) drinking water quality guidelines. The ranges of concentration for the physical parameters analyzed were; pH: (5.8 – 7.7), EC: (5.08 – 35.6 µS/cm),  TDS: (1.68 – 20.16 mg/L, Ca: (0.163 – 24.331 mg/L), Cr: (VI) : (BDL – 0.029 mg/L), Cu: (BDL - 0.085 mg/L); Fe: (BDL – 0.068), anions were SO42- : (BDL – 5.00 mg/L) and F- : (BDL – 0.5 mg/L). Nevertheless, there was no significant difference for the measured parameters between urban and rural areas. This is a good indication that the air quality in Zanzibar is remarkably not polluted with respect to the parameters studied

Toxoplasma gondii peroxiredoxin promotes altered macrophage function, caspase-1-dependent IL-1β secretion enhances parasite replication

Alternatively activated macrophages (AAM) are a key feature Th2 immunity and have been associated with a variety of roles during helminth infection. The role this cell subset plays in protzoan infection remain relatively unexplored, herein we describe the effects of a redox enzyme (rTgPrx) derived from Toxoplasma gondii on murine macrophage phenotype in vitro. RTgPrx has been previously associated with the maintainence of parasite oxidative balance. Here our experiments show that rTgPrx promotes AAM as indicated by high arginase-1 (arg-1), YM1 and FIZZ expression via both signal transducer and activator of transcription (STAT)6-dependent and -independent mechanisms. Additionally rTgPrx treatment reduced caspase-1 activity and IL-1β secretion, while simultaneously increasing IL-10 release. Furthermore the in vitro replication of T. gondii (RH strain) was enhanced when macrophages were treated with rTgPrx. This is in contrast with the previously described effects of a Plasmodium berghei ANKA 2-cys-peroxiredoxin that promotes pro-inflammatory cytokine production. These results highlight the role of T. gondii derived redox enzymes as important immune modulators and potentially indicate a role for AAM in modulating immunopathology and promoting parasite replication during T. gondii infection

Forced evictions and their social and health impacts in Southern Somalia: a qualitative study in Mogadishu Internally Displaced Persons (IDP) camps

Background: Forced evictions are common in conflict-affected settings. More than 500 internally displaced persons (IDPs) are evicted daily in Mogadishu. Context specific research is necessary to inform responsive humanitarian interventions and to monitor the effective- ness of these interventions on IDPs health. Objective: This study explored the causes of forced evictions and their health impacts among IDPs in southern Somalia. Methods: We used a qualitative approach, conducting 20 semi-structured interviews, six key informant interviews and four focus group discussions. We used maximum variation sampling to include a wide range of participants and used the framework approach and Nvivo software to analyse the data. Results: In this context, landlords often rented land without proper tenure agreements, resulting in risk of forced evictions. Informal tenure agreements led to fluctuations in rent, and IDPs were evicted because tenancy laws were inadequate and failed to protect their rights. IDP settlements often increased the value of land by clearing scrub, and landlords often sought to profit from this by evicting IDPs at short notice if a buyer was found for the land. The effect of eviction on an already marginalised population was wide ranging, increasing their exposure to violence, loss of assets, sexual assault, disruption of livelihoods, loss of social networks, and family separation. Evicted IDPs reported health issues such as diarrhoea, malaria, pneumonia, measles and skin infections, as well as stress, anxiety, psychological distress and trauma. Conclusion: Forced evictions remain one of the biggest challenges for IDPs as they exacerbate existing vulnerabilities. Prioritizing implementation of legal protection for IDP tenure rights is necessary to prevent unlawful evictions of IDPs. Humanitarian agencies should aim to respond more effectively to protect evictees and provide support to prevent poor health outcomes. Further quantitative research is needed to examine the relationship between forced evictions and health outcomes