Experimental Investigation of Long-Lived Rydberg States in Ultracold Argon

We report on our investigation of the formation and survival of long-lived Rydberg states in argon produced by pulsed laser excitation of ultracold metastable state argon atoms in a magneto-optical trap. The states studied have a 2P1/2 core. Low angular momentum Rydberg states with this core normally autoionize rapidly. If, however, atoms are excited in the presence of electric fields, higher angular momentum states, traditionally termed ZEKE states (ZEKE is derived from zero kinetic energy) can be formed. The lifetime of these states can be orders of magnitude greater than low angular momentum states. In this paper, we report on the time dependence of ZEKE Rydberg state population in an ultracold environment

MELK-a conserved kinase: functions, signaling, cancer, and controversy.

Maternal embryonic leucine zipper kinase (MELK) is a highly conserved serine/threonine kinase initially found to be expressed in a wide range of early embryonic cellular stages, and as a result has been implicated in embryogenesis and cell cycle control. Recent evidence has identified a broader spectrum of tissue expression pattern for this kinase than previously appreciated. MELK is expressed in several human cancers and stem cell populations. Unique spatial and temporal patterns of expression within these tissues suggest that MELK plays a prominent role in cell cycle control, cell proliferation, apoptosis, cell migration, cell renewal, embryogenesis, oncogenesis, and cancer treatment resistance and recurrence. These findings have important implications for our understanding of development, disease, and cancer therapeutics. Furthermore understanding MELK signaling may elucidate an added dimension of stem cell control

Antimicrobial Activity of Selected Medicinal Plants, \u3cem\u3eCraetva magna\u3c/em\u3e (Linn.), \u3cem\u3ePongamia glabra\u3c/em\u3e (Linn.) and \u3cem\u3eAreca catechu\u3c/em\u3e (Linn.)

Antimicrobial potential in the extracts of three plants. viz. Craetva magna (Linn.), Pongamia glabra (Linn.), Areca catechu (Linn.) that are commonly used by the Kani Tribes of Tirunelveli district, was traced in the present study. The extract of the plant Craetva magna (Linn.), inhibited the growth of pathogenic microbes. Soxhlet extract using chloroform as solvent showed a maximum inhibition of zone formation for the species Salmonella paratyphi (14 mm), and Vibrio cholerae (13 mm) at a concentration of 50 µg/ml. The crude extract of the plant Pongamia glabra (Linn.), showed maximum inhibition for the species Salmonella paratyphi (8 mm), and Vibrio fischeri (8mm) at the concentration of 50 µg/ml. In the Soxhlet-chloroform extract, of Areca catechu the maximum inhibition zone was observed for Vibrio cholerae (14 mm), and Salmonella paratyphi (13 mm). In the present study it was observed that the extracts of the bark of the Craetva magna (Linn.), Pongamia glabra (Linn.), Areca catechu (Linn.), had a broad spectrum antifungal activity

Extended Tuning of an Injection-Locked Diode Laser

We have investigated the application of an electronic feedback technique recently reported by Repasky, et.al. [Appl. Opt. 45, 9013 (2006)] to an injection-locked semiconductor diode laser. We find that without electronic feedback, the injection-locked slave laser will only follow the master for less than 1 GHz, but once the electronic feedback is applied, the slave laser is capable of following for more than 20 GHz, corresponding to the full scan range of the master laser

Fatal Disseminated Herpes Simplex in a very premature neonate

Herpes Simplex Virus infections (HSV) are ubiquitous. The neonatal HSV infection (NHSV) is rare. The incidence is estimated globally at only 10.3 per 100,000 births, but it can cause devastating disease in premature infants. Both HSV-1 and HSV-2 can be the etiologic agents in this type of vertically transmittted NHSV infection. Here we describe the pathological findings from a complete autopsy of a very low birth weight infant who succumbed to the infection despite early institution of antiviral treatment. We urge more awareness of this disease with continued surveillance; every effort should be taken to make an early diagnosis and thus prevent this devastating disease

Importance of controlling diabetes early - The concept of metabolic memory, legacy effect and the case for early insulinisation

Most of the microvascular complications of diabetes are related to the degree and the length of exposure to hyperglycaemia. New data from the follow-up studies of the Diabetes Control and Complications Trial- the Epidemiology of Diabetes Intervention and Complications Study (DCCT- EDIC), and the United Kingdom Prospective Diabetes Study (UKPDS) emphasize the role of glycemic control early in the course of the disorder and its value in prevention of later complications. The phenomenon of ongoing beneficial effects on diabetic complications after a period of improved glycemic control even if followed by a return to usual (often poorer) metabolic control has been described as representing "metabolic memory" by the DCCT/EDIC investigators and as a "legacy effect" by the UKPDS investigators. This article reviews these concepts and explores the role of early use of insulin as a tool to achieve good glycemic control in type 2 diabetes

Pulmonary hypertension occurring with diazoxide use in a preterm infant with hypoglycemia

Pharmacologic modulation to open the KATP channels with diazoxide is useful in treating hyperinsulinemia. Diazoxide is being used more often in neonates with hyperinsulinemic hypoglycemia. This report highlights a case of severe pulmonary hypertension (PH) with re-opening of ductus arteriosus in an extremely premature infant after the use of diazoxide. The rapid onset of PH with respiratory failure was completely reversible. This case emphasizes the need for extreme caution with use of diazoxide in the premature infant population, especially those with chronic lung disease of prematurity. In addition, the use of diazoxide should be limited to the persistent form of congenital hyperinsulinism, after adequate work up has been completed to evaluate for other causes of hypoglycemia. It is postulated that development of PH could be related to KATP agonsim.University of ArizonaOpen access journal.This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Photoassociative Spectroscopy of Ultracold Metastable Argon

We present results of photoassociative spectroscopy performed on ultracold metastable argonatoms in a magneto-optical trap. Ion spectra are obtained with laser detuning up to a few gigahertz below the 4s[3/2]2 → 4p[5/2]3 trapping transition at 811 nm and with intensities in a range of ~(102-105)ISat. We also compute dipole-dipole potentials for both singly and doubly excited diatomic molecules and use a Leroy-Bernstein analysis to determine the approximate vibrational spacings in the (s+p) and (p+p) manifolds. Based on this theoretical framework, we explain a broad background feature in our data and suggest that double-excitation mechanisms are likely responsible for sharp dips in the ion signal

Motion Vector Estimation Search using Hexagon-Diamond Pattern for Video Sequences, Grid Point and Block-Based

Grid and block-based motion vector estimation techniques are proposed for motion tracking in video sequences. The grid technique is referred to the hexagon-diamond pattern. While, block-based technique is referred to 16 × 16 pixels of blocks in a single frame in video sequences. The hexagon and diamond pattern is applied onto the 16 × 16 pixels blocks in a single frame for motion tracking purposes in video sequences. The hexagon grid pattern will conduct a search to capture the motion in a particular block of the hexagon region before the diamond grid pattern takes place for the fine search. The diamond grid pattern provides accuracy to obtain the best grid vector coordinate for motion tracking purposes. The hexagon-diamond grid vector coordinate can be used to determine whether the object is moving toward the horizontal or vertical plane. The information determined at grid vector coordinate can be used as a reference when referring to the previous frame in video sequence processing. The grid vector coordinate will help to determine the area of interest to be examined based on the coordinate obtained. Besides the grid vector estimation, the Point Signal Noise-to-Ratio (PSNR) is also applied to measure the quality of the video

Initial sites of hepadnavirus integration into host genome in human hepatocytes and in the woodchuck model of hepatitis B-associated hepatocellular carcinoma

Hepatitis B virus (HBV) and the closely related woodchuck hepatitis virus (WHV) are potent carcinogens that trigger development of primary hepatocellular carcinoma (HCC). The initial sites of hepadnavirus–host genome integration, their diversity and kinetics of formation can be central to virus persistence and the initiation and progression of HCC. To recognize the nature of the very early virus–host interactions, we explored de novo infection of human hepatocyte-like HepaRG cells with authentic HBV and naive woodchucks with WHV. HepaRG were analyzed from several minutes post exposure to HBV onwards, whereas woodchuck liver biopsies at 1 or 3 h and 6 weeks post infection with WHV. Inverse PCR and clonal sequencing of the amplicons were applied to identify virus–host genomic junctions. HBV and WHV DNA and their replication intermediates became detectable in one hour after virus exposure. Concomitantly, HBV DNA integration into various host genes was detected. Notably, junctions of HBV X gene with retrotransposon sequences, such as LINE1 and LINE2, became prominent shortly after infection. In woodchucks, insertion of WHV X and preS sequences into host genome was evident at 1 and 3 h post infection (h.p.i.), confirming that hepadnavirus under natural conditions integrates into hepatocyte DNA soon after invasion. The HBV and WHV X gene enhancer II/core promotor sequence most often formed initial junctions with host DNA. Moreover, multiple virus–virus DNA fusions appeared from 1 h.p.i. onwards in both infected hepatocytes and woodchuck livers. In summary, HBV DNA integrates almost immediately after infection with a variety of host’s sequences, among which tandemly repeating non-coding DNAs are common. This study revealed that HBV can engage mobile genetic elements from the beginning of infection to induce pro-oncogenic perturbations throughout the host genome. Such swift virus insertion was also evident in natural hepadnaviral infection in woodchucks