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Recent advances in Spectrolab's high efficiency IIIV multi-junction space solar cells are reported. The latest generation GaInP/GaAs/Ge solar cells under productionthe Ultra Triple Junction (UTJ)have an average efficiency at maximum power of 28.0% (AM0, 28C, 135.3?mW/cm2) at beginning of life (BOL), and 22.6% at 60C at end of life (EOL, 15 years in GEO orbit). This represents a 5.5% relative higher efficiency at EOL, compared with the previous generation Improved Triple Junction (ITJ) cells. The P/P0for 1?MeV electrons after 1015?cm-2 fluence has also improved to 0.86, compared with 0.84 for the ITJ cells. These and other performance results of UTJ solar cells are reviewed in comparison with ITJ solar cells. Copyright 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Ticks transmit a large number of pathogens that cause human diseases. Here, the authors sequence the genome of the tick Ixodes scapularisand uncover expansion of genes associated with parasitic processes unique to ticks and tick-host interactions.

Macroporous copper with a complex hyperbolic morphology and superior mechanical properties was produced by replicating the remarkable form of a sea urchin skeletal plate using templated electrochemical deposition. [ABSTRACT FROM AUTHOR]

Syntaxins are a family of membrane-integrated proteins that are instrumental in exocytosis of vesicles. Syntaxin-1 is an essential component of the presynaptic exocytotic fusion machinery in the brain and interacts with several other proteins. Syntaxin-1 forms a four-helical bundle complex with proteins SNAP-25 and VAMP2 that drives fusion of vesicles with the plasma membrane in the active zone. Little is known, however, about the ultrastructural localization of syntaxin-1 at the synapse. We have analysed the intrasynaptic expression of syntaxin-1 in glutamatergic hippocampal synapses in detail by using quantitative postembedding immunogold labeling. Syntaxin-1 was present in highest concentrations at the presynaptic active zone, supporting its role in transmitter release. Presynaptic plasma membrane lateral to the active zone, as well as presynaptic cytoplasmic vesicles were also labeled. However, syntaxin-1 was also significantly expressed in postsynaptic spines, where it was localized at the postsynaptic density, at postsynaptic lateral membranes and in postsynaptic cytoplasm. Postsynaptically, syntaxin-1 colocalized in the nanometer range with the NMDA receptor subunit NR2B, but only weakly with the AMPA receptor subunits GluA2/3. This observation points to the possibility that syntaxin-1 may be involved with NR2B vesicular trafficking from cytoplasmic stores to the postsynaptic plasma membrane, thus facilitating synaptic plasticity. Confocal immunofluorescence double labeling with PSD-95 and ultrastructural fractionation of synaptosomes also confirm localization of syntaxin-1 at the postsynaptic density.

Amaç: Diyare çocuklarda Malawi"yide içeren gelir düzeyi düşük ülkelerde sık görülen problemlerden biridir. Diyare, Cryptosporidium parvum and Isospora belli gibi pek çok intestinal parazitlere bağlı olarak ortaya çıkar. Her iki enfeksiyon Her iki enfeksiyon immune direnci düşük olgularda yaşamı tehdit eden diyareye neden olabilir. Çalışmanın temel amacı QECH başvuran diyaresi olan çocuklar arasında enfeksiyonların bu enfeksiyonların sıklığını araştırmaktır Ayrıca Cryptosporidium parvum ve Isospora belliile enfekte olan insane immuneksikliği virusu (HIV) seropozitif ve HIV seronegatif diyareli çocuklarda hastalığın sıklığı yanı sıra tanı yöntemlerinin değerlendirilmesi amaçlanmıştır. Yöntem: Gaita örnekleri akut diyare (3 günden az) ve diyare olmayan cocuklar hariç kliniğimize kabul edilen ve yatmakta olan diyareli çocuklardan alınmıştır. Her bir örnekten dört yayma hazırlanmıştır: İki tanesi Ziehl,Neelsen boyaması diğer ikisi ise Auramine-Fenol boyaması ile incelenmiştir. Elde edilen veriller Microsoft Excel programına kaydedilip, Epi-Info programı kullanılarak analiz edilmiştir. Bulgular: Beş yaşın altında diyareli 25 çocuk çalışmaya dahil edildi. Bunlardan 10 tanesi HIV seropozitif, 7 tanesi HIV seronegatif 8 tanesinin ise durumu bilinmiyordu. 4 çocukta (16%) cryptosporidium parvum güven aralıkları %4.5 ve %36.1 arası ve hiçbir çocukta Isospora belli tespit edilemedi %0.0 ve %86.3 güven aralıklarında. Cryptosporidium parvum tespit edilen 4 çocuğun 3 tanesi HIV-seropozitif frekansı %30, 1 tanesi ise HIV-seronegatifti frekansı ise %14.3 idi. HIV durumu bilinmeyen çocukların hiç birinde enfeksiyon tespit edilmedi. Sonuç: Modifiye edilmiş Ziehl-Neelsen tekniği ve Auramine-Fenol boyaması QECH"e gelen gaita örneklerinin C.parvum and I.belli tespitinde kullanılabilir. Her nekadar, I.belli bizim bölgemizde yaygın olsada çocuklarda tespit edilmemiştir. Ayrıca bu organizmaların endemik patojen olarak evrimleşmedikleri ve halen yetişkinlerde fırsatçı endemik patojenler olarak hayatlarını sürdürdükleri tespit edilmiştir. Bu çalışmanın özellikle altın standart olarak kabul edilen metodlarla yağmurlu sezonda tekrarlanması gerektiği düşünülmektedir. Anahtar Kelimeler:

Purpose: Diarrhoea in children is a common problem in low resourced countries including Malawi. It is caused by many intestinal parasites including Cryptosporidium parvum and Isospora belli. Both infections are prevalent in severely immunocompromised individuals and may cause severe life-threatening diarrhoea. The main aim of the study was to assess the prevalence of Cryptosporidium parvum and Isospora belli infections among children presenting with diarrhoea admitted to QECH - paediatrics wards and methods used for diagnosis. Some specific objectives were to determine the prevalence of Cryptosporidium parvum and Isospora belli infections among human immunodeficiency virus (HIV) seropositive and HIV seronegative children with diarrhoea, to evaluate diagnostic methods used at QECH to identify intestinal parasites and to determine diagnostic methods that can be recommended for implementation. Methods: Faecal samples were collected from all children presenting with diarrhoea upon admission or already hospitalised were recruited excluding all children without or with acute diarrhoea (less than three days). Four smears were prepared from each sample: 2 for Ziehl Neelsen staining and the other 2 for Auramine-phenol staining. The data was entered into Microsoft Excel and analysed using Epi-Info. Results: A total of 25 children with diarrhoea under the age of five years; 10 were human immunodeficiency virus -seropositive, 7 were HIV-seronegative and 8 of them their status was unknown. Cryptosporidium parvum was detected in 4 children (16%) at 4.5% and 36.1% confidence intervals and none had Isospora belli at 0.0% and 86.3% confidence intervals. Out of those 4 who had Cryptosporidium parvum, 3 children were HIV-seropositive and 1 child was HIV-seronegative at a frequency of 30% and 14.3% respectively. No infection was seen in children whose HIV-serostatus was unknown. Conclusion: Modified Ziehl Neelsen technique and auramine-phenol staining can be used to examine stool at QECH for C.parvum and I.belli identification. Although I.belli is prevalent in our environment, it has not yet been detected in children and or evolved as an endemic pathogen and so far remains as an opportunistic pathogen in adults only. There is need to repeat the study in rainy season and include gold standard method. [Cukurova Med J 2012; 37(3.000): 133-138]

Apolipoprotein E (apoE) associates with lipoproteins and mediates their interaction with members of the LDL receptor family. ApoE exists as three common isoforms that have important distinct functional and biological properties. Two apoE isoforms, apoE3 and apoE4, are recognized by the LDL receptor, whereas apoE2 binds poorly to this receptor and is associated with type III hyperlipidemia. In addition, the apoE4 isoform is associated with the common late-onset familial and sporadic forms of Alzheimer's disease. Although the interaction of apoE with the LDL receptor is well characterized, the specificity of other members of this receptor family for apoE is poorly understood. In the current investigation, we have characterized the binding of apoE to the VLDL receptor and the LDL receptor-related protein (LRP).Our results indicate that like the LDL receptor, LRP prefers lipid-bound forms of apoE, but in contrast to the LDL receptor, both LRP and the VLDL receptor recognize all apoE isoforms. Interestingly, the VLDL receptor does not require the association of apoE with lipid for optimal recognition and avidly binds lipid-free apoE. It is likely that this receptor-dependent specificity for various apoE isoforms and for lipid-free versus lipid-bound forms of apoE is physiologically significant and is connected to distinct functions for these receptors.

Myriapods (e.g., centipedes and millipedes) display a simple homonomous body plan relative to other arthropods. All members of the class are terrestrial, but they attained terrestriality independently of insects. Myriapoda is the only arthropod class not represented by a sequenced genome. We present an analysis of the genome of the centipede Strigamia maritima. It retains a compact genome that has undergone less gene loss and shuffling than previously sequenced arthropods, and many orthologues of genes conserved from the bilaterian ancestor that have been lost in insects. Our analysis locates many genes in conserved macro-synteny contexts, and many small-scale examples of gene clustering. We describe several examples where S. maritima shows different solutions from insects to similar problems. The insect olfactory receptor gene family is absent from S. maritima, and olfaction in air is likely effected by expansion of other receptor gene families. For some genes S. maritima has evolved paralogues to generate coding sequence diversity, where insects use alternate splicing. This is most striking for the Dscam gene, which in Drosophila generates more than 100,000 alternate splice forms, but in S. maritima is encoded by over 100 paralogues. We see an intriguing linkage between the absence of any known photosensory proteins in a blind organism and the additional absence of canonical circadian clock genes. The phylogenetic position of myriapods allows us to identify where in arthropod phylogeny several particular molecular mechanisms and traits emerged. For example, we conclude that juvenile hormone signalling evolved with the emergence of the exoskeleton in the arthropods and that RR-1 containing cuticle proteins evolved in the lineage leading to Mandibulata. We also identify when various gene expansions and losses occurred. The genome of S. maritima offers us a unique glimpse into the ancestral arthropod genome, while also displaying many adaptations to its specific life history.