Ultrafast Charge Transfer at a Quantum Dot/2D Materials Interface Probed by Second Harmonic Generation

Hybrid quantum dot (QD) / transition metal dichalcogenide (TMD) heterostructures are attractive components of next generation optoelectronic devices, which take advantage of the spectral tunability of QDs and the charge and exciton transport properties of TMDs. Here, we demonstrate tunable electronic coupling between CdSe QDs and monolayer WS$_2$ using variable length alkanethiol ligands on the QD surface. Using femtosecond time-resolved second harmonic generation (SHG) microscopy, we show that electron transfer from photoexcited CdSe QDs to single-layer WS$_2$ occurs on ultrafast (50 fs - 1 ps) timescales. Moreover, in the samples exhibiting the fastest charge transfer rates ($\leq$ 50 fs) we observed oscillations in the time-domain signal corresponding to an acoustic phonon mode of the donor QD, which coherently modulates the SHG response of the underlying WS$_2$ layer. These results reveal surprisingly strong electronic coupling at the QD/TMD interface and demonstrate the usefulness of time-resolved SHG for exploring ultrafast electronic-vibrational dynamics in TMD heterostructures

Aggressive Metastatic Translocation Renal Carcinoma in a 23-year-old Man

AbstractTranslocation renal carcinomas are a rare subtype of renal cell carcinoma that typically occurs in young patients, especially those who have received prior chemotherapy. We present the case of a 23-year-old man with abdominal pain, nausea vomiting and neck swelling. Contrast enhanced computed tomography (CECT) of the neck, chest, abdomen and pelvis showed extensive left supraclavicular adenopathy, as well as extensive retroperitoneal adenopathy, displacing the pancreas superiorly, as well as encasing the aorta

Wireless sensor network’s localization based on multiple signal classification algorithm

Wireless sensor networks (WSNs) are a number of sensitive nodes senses a physical phenomenon at the position of their deployment then sends information to the base station to take appropriate operation. (WSNs) are used in many applications such track military targets, discover fires, study natural phenomena such as earthquakes, humidity, heat, etc. The nodes are spread in large areas and it is difficult to locate them manually because they are published randomly by planes or any other method and since the information received from sensitive nodes is useless without knowing their location in this case a problem resulted in the positioning of the nodes. So it unacceptable to equip each sensor node with global position system (GPS) due to various problems such as raises cost and energy consumption. In this paper explained a non-GPS technique to self-positioning of nodes in (WSNs) by using the multiple signal classification (MUSIC) algorithm to determine the position of the active sensor through estimated the direction of arrival (DOA) of the node signal. Then modified MUSIC algorithm (M-MUSIC) to solve the problem of coherent signal. MATLAB program successfully used to simulate the proposed algorithm

Thermal-Hydrodynamic Characteristics of Turbulent Flow in Corrugated Channels

The heat transfer-flow characteristics of turbulent flow inside corrugated channels heated by constant heat flux are numerically investigated. The rate of heat transfer, pressure drop, and performance evaluation criterion is determined for smooth channel and various designs of corrugated channels at the Reynolds number ranged from 5000 to 60,000. The effect of rib arrangement distributions of inward, outward, and inward-outward ribs are examined. The various rib configurations of corrugated channels are also tested. In addition, the influences of rib roughness parameters (height, pitch, and width) and rib shapes (semicircular, trapezoidal, and rectangular) are researched. The Reynolds-averaged Navier-Stokes equations (RANS) are used to model the governing flow equations. The computational model is validated through a reasonable agreement between the present numerical results and the outcomes of related works. For different geometrical and operating conditions, the results revealed that the rate of heat exchange in corrugated channels exceeds higher than that of smooth ones but with additional pressure loss. Moreover, the rib arrangements, rib configuration, and rib roughness parameters exhibit a relatively significant effect on the performance of the corrugated channels. On the other hand, the influence of the rib shapes seems to be small

Molecular Serotyping of Cryptococcus neoformans Isolated from Environmental Sources

بالإضافة الى معرفة لمورث (الكبسولة 59) باستعمال تقنية تفاعل سلسلة انزيم البلمرة في نماذج العزلات المأخوذة من مصادر بيئية مختلفة وكذلك هدفت الدراسة الحالية الى التنميط الجزيئي ضمن عزلات من مصادر بيئية مختلفة لخميرة المكورات الخبيئة ، باستخدام بعض التقنيات المظهرية والجزيئية. تعتبر خميرة المكورات الخبيئة من الفطريات البازيدية المعزولة من مصادر بيئية مختلفة والتي قد تسبب مشاكل صحية خطيرة للانسان وبالاخص المرضى المثبطين مناعياً، وقد صممت هذه الدراسة للتحري عن التنميط الجزيئي لخمائر المكورات الخبيئة على المستوى الوراثي لتحديد الانماط المصلية العائدة لهذه الخميرة والتمييز بينها. وللدراسة الجزيئية لجين الكابسولة (المحفظة) المتعددة السكريات باستخدام فحص تفاعل سلسلة انزيم البلمرة تضمن أيضاً التشخيص بالطرق الجزيئية، فقد تم استخدام طريقة تفاعل سلسلة انزيم البلمرة لتشخيص النمط المصلي للخميرة بصورة وراثية بالاعتماد على تضخيم الـ DNA. تم تشخيص العزلات كخميرة المكورات الخبيئة، فضلاً عن ذلك كان النوع الاكثر تردداً هو neoformans  بلغ العدد الكلي بينما النوع gattii وكان الاقل تردداً. اظهرت نتائج تضخيم الـ DNA، باستخدام البادئ المتخصص، حزم بأوزان جزيئية (387 زوج قاعدة) لـ (12) عزلة, على اية حال النوع الثاني اظهر حزم بوزن جزيئي (359 زوج قاعدة). كما وتم تشخيص العزلات بصورة وراثية على مستوى نمط مصلي باستخدام طريقة RFLP مع الانزيمات القاطعة (Bsm F1) و (Hpa II) والتي من خلالها ظهرت معلومات مهمة للعزلات المدروسة التي هي متعلقة بالنوعين من الخميرة المدروسة. اظهر اختبار تفاعل سلسلة انزيم البلمرة خمسة انماط مصلية مختلفة كانت محددة، النمط المصلي A ,النمط المصلي B النمط المصلي C النمط المصلي D والنمط المصلي AD وكانت الاختلافات معنوية قد ظهرت بين الانماط المصلية المختلفة. ومن هذا نستنتج بان اختبار تفاعل سلسلة انزيم البلمرة كان مهدفاً الـ DNA النووي وكان اختبار RFLP سريعاً وبسيطاً تقنياً لتنميط الخميرة جزيئياُ ومقيداً ليس فقط لتفريق الخميرة عن الانواع ذات العلاقة بها ولكن مفيد ايضاً للدراسات الوبائية على المستوى الجزيئي. هذه الدراسة وفرت التنميط المصلي بصورة جزيئية لخميرة المكورات الخبيئة المعزولة من مصادر بيئية مختلفة في محافظة النجف. نستنتج من هذه الدراسة بأن خميرة المكورات الخبيئة من الفطريات المرضية المنتهزة للفرص، ولها دور اساسي في احداث المرض في الكائنات (المضائف) المعتلة مناعياً – او المثبطة مناعياً – والذي تم تأكيد تشخيصه في هذه الدراسة باستعمال بادئات خاصة بهذه الخميرة.In addition to study the genetic information of capsular polysaccharide gene by PCR assay .This study is also, aimed to determine the molecular serotyping among different environmental resources samples of Cryptococcus neoformans, by using phenotypic and molecular techniques. So, this study is designed to investigate the molecular serotyping of C. neoformans at a genetic level in order to identify the serotypes belong to this yeast and to differentiate them from each other. To achieve these goals, environmental resources samples were collected from different area of Najaf province during (2015). Culture tests are done for samples in The same aspect includes  identification by molecular methods. The polymerase chain reaction method (PCR) is used to identify the Cryptococcus serotype genetically. Depending on amplification of genomic DNA, the entire isolates are diagnosed as Cryptococcus yeasts. However, the most recurring species are the C. neoformans that rated 80%, while the C. gattii that rated 20% is the less recurring one. The results of amplifing the genomic DNA, using specific primer, show bands with molecular weight that is (387 bp) approximately for 12 isolates. However, the other species showed band with molecular weight that was (359 bp). The  isolates are diagnosed genetically using the RFLP – PCR method as restriction enzyme with (Bsm F1, Hpa II) through which systematic important information appears for the genetic relations in the studied isolates that are related for two types. PCR assay revealed that five different serotypic patterns are detected as: serotype A ,serotype B , serotype C , serotype D and serotype AD .It can be concluded that the PCR targeting the genomic DNA and the REFP – PCR are rapid and simple techniques for serotyping C. neoformans and are useful not only for discrimination of C. neoformans from its related species, but also for epidemiological study at the molecular level. This study provides the detection genetically serotyping of C. neoformans which is isolated from different environmental resources in Najaf provinc

Early Onset Neonatal Sepsis: Bacteriological Antimicrobial Susceptibility Study in Duhok Province, Iraq

        Early neonatal infection is obvious problem resulting in significant morbidity and mortality especially preterm neonates, therefore rapid diagnosis and early treatment paramount to avoid death. The current study was design to determine the frequency of bacterial isolates causing early onset neonatal sepsis and their susceptibility patterns in Duhok province, in which carried out on newborns were admitted to the preterm unit and intensive care unit (ICU) in Maternity & Obstetric Hospital in Duhok/ Iraq, from November 2015 to December 2016. Patients were classified in to two groups (proven and clinical sepsis) according to the clinical signs and blood culture.                                                                                                                       Collected blood samples were cultured in Brain Heart Infusion broth and check daily for 3 days for presence of visible microbial growth. Then all purified isolates were confirmed by using BD- Phoenix™ identification and susceptibility testing system     provides rapid, accurate and reliable detection of known and emerging antimicrobial   resistance. All data obtained, were analyzed by SPSS version 23 windows and Microsoft Excel (2013). One-hundred twenty neonates were studied and the proven sepsis was found in 91(75.8%) cases, while 29 (24.1%) cases reported as negative blood culture. Gram negative bacteria were responsible for most cases of neonatal sepsis 62(68.1%) while Gram positive bacteria were 29(31.9%). The most frequent isolated pathogens were Klebsiella pneumoniae 30(33%), Coagulase negative Staphylococcus 24(26.4%), Escherechia coli 19 (20.9%), Pseudomonas aeruginosa 9 (9.9%), followed by Enterobacter aerogenes and Streptococcus agalactiae 3(3.3%), Enterococcus faecalis 2(2.2%), and one isolate of Shigella dysenteriae (1.1%). In conclusion: EOS mainly associated with gram negative bacteria, Klebsiella pneumoniae found to be the predominant pathogens. The result of our study reveals that all isolates (both gram negative and gram positive bacteria) were multidrug resistant.                                                                                                                           &nbsp

A genetic basis for a postmeiotic X versus Y chromosome intragenomic conflict in the mouse.

Intragenomic conflicts arise when a genetic element favours its own transmission to the detriment of others. Conflicts over sex chromosome transmission are expected to have influenced genome structure, gene regulation, and speciation. In the mouse, the existence of an intragenomic conflict between X- and Y-linked multicopy genes has long been suggested but never demonstrated. The Y-encoded multicopy gene Sly has been shown to have a predominant role in the epigenetic repression of post meiotic sex chromatin (PMSC) and, as such, represses X and Y genes, among which are its X-linked homologs Slx and Slxl1. Here, we produced mice that are deficient for both Sly and Slx/Slxl1 and observed that Slx/Slxl1 has an opposite role to that of Sly, in that it stimulates XY gene expression in spermatids. Slx/Slxl1 deficiency rescues the sperm differentiation defects and near sterility caused by Sly deficiency and vice versa. Slx/Slxl1 deficiency also causes a sex ratio distortion towards the production of male offspring that is corrected by Sly deficiency. All in all, our data show that Slx/Slxl1 and Sly have antagonistic effects during sperm differentiation and are involved in a postmeiotic intragenomic conflict that causes segregation distortion and male sterility. This is undoubtedly what drove the massive gene amplification on the mouse X and Y chromosomes. It may also be at the basis of cases of F1 male hybrid sterility where the balance between Slx/Slxl1 and Sly copy number, and therefore expression, is disrupted. To the best of our knowledge, our work is the first demonstration of a competition occurring between X and Y related genes in mammals. It also provides a biological basis for the concept that intragenomic conflict is an important evolutionary force which impacts on gene expression, genome structure, and speciation

Recall errors in a weekly survey of diarrhoea in Guatemala: determining the optimal length of recall

We measured the recall error, optimal recall length and factors associated with diarrhoea in a weekly survey. Data was taken from a year-long randomized controlled trial in which characteristics of diarrhoeal episodes were recorded weekly. We labelled the recall period as days 1-6, day I being the day before the visit. Recall error was the percentage difference between the number of episodes reported to begin on a particular day and the mean for days I and 2. Generalized estimating equations were used to determine associations. Recall error was 37% on day 3 and 51% on day 5. The error was less in younger children (by 10%), severe episodes (by 29%) and when blood was present in the stool (by 18%). Diarrhoea was underreported when the recall period extended beyond 2 days. Surveys that use longer recall periods risk underestimating diarrhoea incidence and selectively capturing more severe episodes

The multicopy gene Sly represses the sex chromosomes in the male mouse germline after meiosis.

Studies of mice with Y chromosome long arm deficiencies suggest that the male-specific region (MSYq) encodes information required for sperm differentiation and postmeiotic sex chromatin repression (PSCR). Several genes have been identified on MSYq, but because they are present in more than 40 copies each, their functions cannot be investigated using traditional gene targeting. Here, we generate transgenic mice producing small interfering RNAs that specifically target the transcripts of the MSYq-encoded multicopy gene Sly (Sycp3-like Y-linked). Microarray analyses performed on these Sly-deficient males and on MSYq-deficient males show a remarkable up-regulation of sex chromosome genes in spermatids. SLY protein colocalizes with the X and Y chromatin in spermatids of normal males, and Sly deficiency leads to defective repressive marks on the sex chromatin, such as reduced levels of the heterochromatin protein CBX1 and of histone H3 methylated at lysine 9. Sly-deficient mice, just like MSYq-deficient mice, have severe impairment of sperm differentiation and are near sterile. We propose that their spermiogenesis phenotype is a consequence of the change in spermatid gene expression following Sly deficiency. To our knowledge, this is the first successful targeted disruption of the function of a multicopy gene (or of any Y gene). It shows that SLY has a predominant role in PSCR, either via direct interaction with the spermatid sex chromatin or via interaction with sex chromatin protein partners. Sly deficiency is the major underlying cause of the spectrum of anomalies identified 17 y ago in MSYq-deficient males. Our results also suggest that the expansion of sex-linked spermatid-expressed genes in mouse is a consequence of the enhancement of PSCR that accompanies Sly amplification

DEVELOPMENT OF A REVERSED PHASE - HPLC METHOD FOR DETERMINATION OF MELOXICAM IN TABLET FORMULATION AND HUMAN SERUM

Developing a simple, economic, sensitive and rapid isocratic RPHPLC method for determination of meloxicam (MX) in bulk drug, tablet formulation and human serum. The retention time observed for meloxicam was just 2.35 minutes using C18 column (150 x 3.0 mm, 5 μm) with a mobile phase consisting of acetonitrile: 0.2% formic acid (70:30 v/v%) at a flow rate of 1 ml/min with UV detector set at 355 nm. Linearity in concentration range of 0.05 – 50 µg/ml, with coefficient of determination, R² = 0.9956; slope= 25464 and intercept= -8872. The limit of detection and the limit of quantification were found to be 0.011 and 0.173 μg/ml, respectively. The precision and accuracy of method were checked by calculating RSD% and relative error E%, which were found to be reasonable. A RSD% (0.06 and 0.021%) for marketed brand and human serum, respectively and E% (0.64 and -0.47 %) for marketed brand and human serum, respectively. The method was found to be applicable for the analysis of MX in bulk, tablet formulation and human seru