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A beam containing a substantial component of both the $J^{\pi}=5^+$, $T_{1/2}=162$ ns isomeric state of $^{18}$F and its $1^+$, 109.77-min ground state has been utilized to study members of the ground-state rotational band in $^{19}$F through the neutron transfer reaction $(d$,$p)$ in inverse kinematics. The resulting spectroscopic strengths confirm the single-particle nature of the 13/2$^+$ band-terminating state. The agreement between shell-model calculations, using an interaction constructed within the $sd$ shell, and our experimental results reinforces the idea of a single-particle/collective duality in the descriptions of the structure of atomic nuclei.

We report the first observation of the 108Xe→104Te→100Sn α-decay chain. The α emitters, 108Xe [Eα=4.4(2) MeV, T1/2=58+106−23 μs] and 104Te [Eα=4.9(2) MeV, T1/2100Sn were produced using a fusion-evaporation reaction 54Fe(58Ni,4n)108Xe, and identified with a recoil mass separator and an implantation-decay correlation technique. This is the first time α radioactivity has been observed to a heavy self-conjugate nucleus. A previous benchmark for study of this fundamental decay mode has been the decay of 212Po into doubly magic 208Pb. Enhanced proton-neutron interactions in the N=Z parent nuclei may result in superallowed α decays with reduced α-decay widths significantly greater than that for 212Po. From the decay chain, we deduce that the α-reduced width for 108Xe or 104Te is more than a factor of 5 larger than that for 212Po.© 2018 American Physical Society

We have presented an algorithm of digital image watermarking for gray scale images which we implemented in frequency domain. Before inserting the watermark, we added the Hamming codes row wise as well column wise. Two encryption techniques were implemented on the ECC inserted watermark for its security. The pixel position for inserting the watermark was calculated using starting row and column number for that 8×8 block. Pixel embedding strength is calculated using criteria that low frequency is robust in general signal processing attacks, thus choosing less value to be embedded and vice-versa. Results show that the watermarking algorithm is robust against common signal processing attacks. The algorithm is tested against multiple attacks also.

This study presented an algorithm to protect the copyright watermark by providing Hamming codes as error correcting technique. Watermark was embedded in frequency domain using discrete cosine transformation and discrete wavelet transformation, to enhance the susceptibility. Combinations of two techniques are used to target medium frequencies only. Randomness of the watermark is also created before embedding. Instead of embedding in the same place in every block, it is embedded adaptively which depends upon the row and column of that particular block. Results prove the effectiveness of the algorithm against various attacks like jpeg attack, filtering and addition of noises like Gaussian noise, salt and pepper noise and speckle noise. ECC proved to be effective to recover the watermark after certain attacks performed.

Background: The $^{22}\mathrm{Ne}(\ensuremath{\alpha},n)^{25}\mathrm{Mg}$ reaction is the dominant neutron source for the slow neutron capture process ($s$ process) in massive stars, and contributes, together with $^{13}\mathrm{C}(\ensuremath{\alpha},n)^{16}\mathrm{O}$, to the production of neutrons for the $s$ process in asymptotic giant branch (AGB) stars. However, the reaction is endothermic and competes directly with $^{22}\mathrm{Ne}(\ensuremath{\alpha},\ensuremath{\gamma})^{26}\mathrm{Mg}$ radiative capture. The uncertainties for both reactions are large owing to the uncertainty in the level structure of $^{26}\mathrm{Mg}$ near the $\ensuremath{\alpha}$ and neutron separation energies. These uncertainties affect the $s$-process nucleosynthesis calculations in theoretical stellar models.Purpose: Indirect studies in the past have been successful in determining the energies and the $\ensuremath{\gamma}$-ray and neutron widths of the $^{26}\mathrm{Mg}$ states in the energy region of interest. But, the high Coulomb barrier hinders a direct measurement of the resonance strengths, which are determined by the $\ensuremath{\alpha}$ widths for these states. The goal of the present experiments is to identify the critical resonance states and to precisely measure the $\ensuremath{\alpha}$ widths by $\ensuremath{\alpha}$-transfer techniques.Methods: The $\ensuremath{\alpha}$-inelastic scattering and $\ensuremath{\alpha}$-transfer measurements were performed on a solid $^{26}\mathrm{Mg}$ target and a $^{22}\mathrm{Ne}$ gas target, respectively, using the Grand Raiden Spectrometer at the Research Center for Nuclear Physics in Osaka, Japan. The $(\ensuremath{\alpha},{\ensuremath{\alpha}}^{\ensuremath{'}})$ measurements were performed at $0.{45}^{\ensuremath{\circ}}, 4.{1}^{\ensuremath{\circ}}, 8.{6}^{\ensuremath{\circ}}$, and $11.{1}^{\ensuremath{\circ}}$ and the $(^{6}\mathrm{Li},d)$ measurements at ${0}^{\ensuremath{\circ}}$ and ${10}^{\ensuremath{\circ}}$. The scattered $\ensuremath{\alpha}$ particles and deuterons were detected by the focal plane detection system consisting of multiwire drift chambers and plastic scintillators. The focal plane energy calibration allowed the study of $^{26}\mathrm{Mg}$ levels from ${E}_{x}$ = 7.69--12.06 MeV in the $(\ensuremath{\alpha},{\ensuremath{\alpha}}^{\ensuremath{'}})$ measurement and ${E}_{x}$ = 7.36--11.32 MeV in the $(^{6}\mathrm{Li},d)$ measurement.Results: Six levels (${E}_{x}$ = 10717, 10822, 10951, 11085, 11167, and 11317 keV) were observed above the $\ensuremath{\alpha}$ threshold in the region of interest (10.61--11.32 MeV). The $\ensuremath{\alpha}$ widths were calculated for these states from the experimental data. The results were used to determine the $\ensuremath{\alpha}$-capture induced reaction rates.Conclusion: The energy range above the $\ensuremath{\alpha}$ threshold in $^{26}\mathrm{Mg}$ was investigated using a high resolution spectrometer. A number of states were observed for the first time in $\ensuremath{\alpha}$-scattering and $\ensuremath{\alpha}$-transfer reactions. The excitation energies and spin-parities were determined. Good agreement is observed for previously known levels in $^{26}\mathrm{Mg}$. From the observed resonance levels the ${E}_{x}$ = 10717 keV state has a negligible contribution to the $\ensuremath{\alpha}$-induced reaction rates. The rates are dominated in both reaction channels by the resonance contributions of the states at ${E}_{x}$ = 10951, 11167, and 11317 keV. The ${E}_{x}$ = 11167 keV state has the most appreciable impact on the $(\ensuremath{\alpha},\ensuremath{\gamma})$ rate and therefore plays an important role in the prediction of the neutron production in $s$-process environments.

Introduction Kidney transplants have become common surgical procedures, with thousands performed yearly around the world. Surgical complications in renal transplantation result in significant morbidity to the recipient, with risk of graft loss and mortality. Material and methods We retrospectively analyzed 720 cases of renal transplantation done at our center from 1991 to July 2010. The standard techniques of vascular anastomosis and extravesical stented ureteroneocystostomy were used. Results Mean age at the time of transplantation was 33 years (range 5–67 years) and majority were male (558/720). Live related donor renal transplantation was performed in 684 and deceased donor kidney transplantation in 36 patients. The incidence of ureter related major complication was urinary leak in seven (0.97%) cases and intrinsic ureteral obstruction in two (0.27%) cases. Vascular complications occurred in nine cases including four cases of venous thrombosis of which two could be salvaged. Four grafts were lost due to arterial thrombosis and one due to arterial anastomotic dehiscence. Conclusion Routine use of ureteric stent seems to reduce the rate of urinary complications. Meticulous tying of all lymphatics tends to reduce the incidence of obstructing lymphocele. Early diagnosis and prompt surgical treatment of urological and vascular complications helps in salvaging the grafts.

Neutrons produced by the carbon fusion reaction (12)C((12)C,n)(23)Mg play an important role in stellar nucleosynthesis. However, past studies have shown large discrepancies between experimental data and theory, leading to an uncertain cross section extrapolation at astrophysical energies. We present the first direct measurement that extends deep into the astrophysical energy range along with a new and improved extrapolation technique based on experimental data from the mirror reaction (12)C((12)C,p)(23)Na. The new reaction rate has been determined with a well-defined uncertainty that exceeds the precision required by astrophysics models. Using our constrained rate, we find that (12)C((12)C,n)(23)Mg is crucial to the production of Na and Al in pop-III pair instability supernovae. It also plays a nonnegligible role in the production of weak s-process elements, as well as in the production of the important galactic γ-ray emitter (60)Fe.

Funding Details: PHY 08-22648, NSF, National Science Foundation; PHY 0969058, NSF, National Science Foundation; PHY 1102511, NSF, National Science Foundation

The surgical treatment of adult anterior urethral strictures is constantly evolving. Controversy exists over the best means of reconstructing the anterior urethra.Twelve patients underwent buccal mucosal urethroplasty for long segment anterior urethral stricture between 2003 and 2005 . Eleven patients with a salvageable urethral plate were treated with one stage dorsal onlay urethroplasty, using a perineal or circumcoronal incision. One patient with a severely scarred urethral plate underwent two-stage urethroplasty.At a mean follow up of 14.2 months (range 2 to 26) one (8.3%) patient had short recurrent stricture, which was treated with optical urethrotomy. The mean maximal urine flow rate improved from 8.3 ml/sec to 18.1 ml/sec after the surgery. There were no donor site complications. All patients had a normal slit like meatus and none had chordee or erectile dysfunction.In long stricture of anterior urethra, dorsal onlay buccal mucosa urethroplasty provides excellent intermediate term results with a normal, wide caliber urethra.

Using inelastic $\alpha$-scattering at extremely forward angles, including $0^\circ$, the strength distributions of the isoscalar giant monopole resonance (ISGMR) have been measured in the $^{204,206,208}$Pb isotopes in order to examine the proposed mutually enhanced magicity (MEM) effect on the nuclear incompressibility. The MEM effect had been suggested as a likely explanation of the "softness" of nuclear incompressibility observed in the ISGMR measurements in the Sn and Cd isotopes. Our experimental results rule out any manifestation of the MEM effect in nuclear incompressibility and leave the question of the softness of the open-shell nuclei unresolved still., Comment: Accepted for publication in Physics Letters B. Very minor changes in text

Background: The reaction ${}^{18}$O${(\ensuremath{\alpha},n)}^{21}$Ne is a part of the reaction chains leading to the production of ${}^{19}$F and ${}^{22}$Ne during He burning in low-mass and massive AGB stars, respectively. Additionally, it has been observed as a strong background source in the measurement of other $(\ensuremath{\alpha},n)$ reactions.Purpose: Previously low-energy ${}^{18}$O${(\ensuremath{\alpha},n)}^{21}$Ne cross section data have only been available in a non-peer-reviewed form. An improved measurement of this reaction has been done to both clarify its astrophysical influence as well as to provide background yield data for future $(\ensuremath{\alpha},n)$ experiments.Method: The ${}^{18}$O$(\ensuremath{\alpha},{n}_{(0+1)})$ reaction has been measured with a moderating neutron detector. In addition the $(\ensuremath{\alpha},{n}_{1}\ensuremath{\gamma})$ channel has been measured independently by observation of the characteristic 350.7 keV $\ensuremath{\gamma}$ transition in ${}^{21}$Ne. The reaction cross section at energies above ${E}_{\ensuremath{\alpha}}=1100$ keV was determined by a simultaneous $R$-matrix fit to both channels. The strengths of the two lowest-energy resonances at ${E}_{\ensuremath{\alpha}}=959$ keV and ${E}_{\ensuremath{\alpha}}=1066$ keV were analyzed separately using individual Breit-Wigner fits.Results: The cross section of both reaction channels, ${}^{18}$O${(\ensuremath{\alpha},{n}_{0})}^{21}$Ne and ${}^{18}$O${(\ensuremath{\alpha},{n}_{1}\ensuremath{\gamma})}^{21}$Ne, was determined from the threshold energies at 851 keV and 1280 keV, respectively, to 2300 keV. A new reaction rate has been deduced for the temperature range of 0.1 GK to 10 GK. A previously reported resonance at ${E}_{\ensuremath{\alpha}}=888$ keV is explained as background from the contaminant reaction ${}^{17}$O${(\ensuremath{\alpha},n)}^{20}$Ne.Conclusions: In general, our reaction rate is slightly lower than the reaction rates in recent compilations. At temperatures below 0.2 GK the present rate is significantly lower because it could be shown that the lowest reported resonance is background from the reaction ${}^{17}$O${(\ensuremath{\alpha},n)}^{20}$Ne that has been wrongly assigned to ${}^{18}$O${(\ensuremath{\alpha},n)}^{21}$Ne.

Background: The ratio between the rates of the reactions ${}^{17}$O${(\ensuremath{\alpha},n)}^{20}$Ne and ${}^{17}$O${(\ensuremath{\alpha},\ensuremath{\gamma})}^{21}$Ne determines whether ${}^{16}$O is an efficient neutron poison for the $s$ process in massive stars, or if most of the neutrons captured by ${}^{16}$O$(n,\ensuremath{\gamma})$ are recycled into the stellar environment. This ratio is of particular relevance to constrain the $s$ process yields of fast rotating massive stars at low metallicity.Purpose: Recent results on the $(\ensuremath{\alpha},\ensuremath{\gamma})$ channel have made it necessary to measure the $(\ensuremath{\alpha},n)$ reaction more precisely and investigate the effect of the new data on $s$ process nucleosynthesis in massive stars.Method: The ${}^{17}$O$(\ensuremath{\alpha},{n}_{(0+1)})$ reaction has been measured with a moderating neutron detector. In addition, the $(\ensuremath{\alpha},{n}_{1})$ channel has been measured independently by observation of the characteristic 1633 keV $\ensuremath{\gamma}$ transition in ${}^{20}$Ne. The reaction cross section was determined with a simultaneous R-matrix fit to both channels. $(\ensuremath{\alpha},n)$ and $(\ensuremath{\alpha},\ensuremath{\gamma})$ resonance strengths of states lying below the covered energy range were estimated using their known properties from the literature.Result: The reaction channels ${}^{17}$O${(\ensuremath{\alpha},{n}_{0})}^{20}$Ne and ${}^{17}$O${(\ensuremath{\alpha},{n}_{1}\ensuremath{\gamma})}^{20}$Ne were measured in the energy range ${E}_{\ensuremath{\alpha}}=800$ keV to 2300 keV. A new ${}^{17}$O$(\ensuremath{\alpha},n)$ reaction rate was deduced for the temperature range 0.1 GK to 10 GK. At typical He burning temperatures, the combination of the new $(\ensuremath{\alpha},n)$ rate with a previously measured $(\ensuremath{\alpha},\ensuremath{\gamma})$ rate gives approximately the same ratio as current compilations. The influence on the nucleosynthesis of the $s$ process in massive stars at low metallicity is discussed.Conclusions: It was found that in He burning conditions the $(\ensuremath{\alpha},\ensuremath{\gamma})$ channel is strong enough to compete with the neutron channel. This leads to a less efficient neutron recycling compared to a previous suggestion of a very weak $(\ensuremath{\alpha},\ensuremath{\gamma})$ channel. $S$ process calculations using our rates confirm that massive rotating stars do play a significant role in the production of elements up to Sr, but they strongly reduce the $s$ process contribution to heavier elements.

Neutrons produced by the carbon fusion reaction (12)C((12)C,n)(23)Mg play an important role in stellar nucleosynthesis. However, past studies have shown large discrepancies between experimental data and theory, leading to an uncertain cross section extrapolation at astrophysical energies. We present the first direct measurement that extends deep into the astrophysical energy range along with a new and improved extrapolation technique based on experimental data from the mirror reaction (12)C((12)C,p)(23)Na. The new reaction rate has been determined with a well-defined uncertainty that exceeds the precision required by astrophysics models. Using our constrained rate, we find that (12)C((12)C,n)(23)Mg is crucial to the production of Na and Al in pop-III pair instability supernovae. It also plays a nonnegligible role in the production of weak s-process elements, as well as in the production of the important galactic γ-ray emitter (60)Fe.

The reaction $^{17}\mathrm{O}$$(\ensuremath{\alpha},\ensuremath{\gamma}){}^{21}$Ne has been measured by in-beam $\ensuremath{\gamma}$ spectroscopy for the first time in the energy range ${E}_{\ensuremath{\alpha}}=750$--1650 keV using highly enriched anodized ${\text{Ta}}_{2}({}^{17}\text{O}){}_{5}$ targets. Resonances were found at ${E}_{\ensuremath{\alpha}}=$ 1002, 1386, and 1619 keV. Their strengths and primary $\ensuremath{\gamma}$-ray branchings are given. The new results exclude the low reaction rate of Descouvemont and support the rate of Caughlan and Fowler. Implications for the neutron poisoning efficiency of $^{16}\mathrm{O}$ in the weak $s$-process are discussed.

Nutritional status of 1661 children aged 6 months to 2 years who attended the Well Baby Clinic of UHC Gokulpuri, Delhi during the year 2000 was studied. 60.7% of them were malnourished. Undesirable practices of discarding the colostrum, not exclusively breast feeding the child till at least 4 months of age, delayed weaning, dilution of top milk, use of bottle and nipple for feeding the children are still widely prevalent.

The hospital records of 58 patients operated on for tuberculous perforations of the small intestines at our hospital between 1987 and 1996 were reviewed. Clinical features were non-specific in the majority of the patients. Pneumoperitoneum on abdominal radiographs was present in only 28 (48.3%) patients. Forty-five (77.6%) were operated on within 36 hours of perforation. Surgical management consisted of resection and end-to-end anastomosis (n = 45); oval excision of the perforation and transverse anastomosis reinforced with an omental patch (n = 7); ileo-transverse colostomy (n = 5); and peritoneal drainage only (n = 1). There were 17 deaths (29.3%). Adverse prognostic factors were operation beyond 36 hours (p0.01), multiple perforations (p0.001), and faecal fistula formation (p0.01). Mortality was least with early resection and end-to-end anastomosis of the perforated bowel segment. We conclude that a high index of suspicion is essential for early diagnosis and optimal treatment of patients with tuberculous intestinal perforations.

The three-dimensional structures of rabbit and human liver cytosolic serine hydroxymethyltransferase revealed that H231 interacts with the O3' of pyridoxal-5'-phosphate and other residues at the active site such as S203, K257, H357 and R402 (numbering as per the human enzyme). This and the conserved nature of H231 in all serine hydroxymethyltransferases highlights its importance in catalysis and/or maintenance of oligomeric structure of the enzyme. In an attempt to decipher the role of H230 (H231 of the human enzyme) in the catalytic mechanism and/or maintenance of oligomeric structure of sheep liver serine hydroxymethyltransferase, the residue was mutated to arginine, phenylalanine, alanine, asparagine or tyrosine. Our results suggest that the nature of the amino acid substitution has a marked effect on the catalytic activity of the enzyme. H230R and H230F mutant proteins were completely inactive, dimeric and did not bind pyridoxal-5'-phosphate. On the other hand, mutation to alanine and asparagine retained the oligomeric structure and ability to bind pyridoxal-5'-phosphate. These mutants had only 2-3% catalytic activity. The side reactions like transamination and 5,6,7, 8-tetrahydrofolate independent aldol cleavage were much more severely affected. They were able to form the external aldimine with glycine and serine but the quinonoid intermediate was not observed upon the addition of 5,6,7,8-tetrahydrofolate. Mutation to tyrosine did not affect the oligomeric structure and pyridoxal-5'-phosphate binding. The H230Y enzyme was 10% active and showed a correspondingly lower amount of quinonoid intermediate. The kcat / Km values for L-serine and Lallothreonine were 10-fold and 174-fold less for this mutant enzyme compared to the wild-type protein. These results suggest that H230 is involved in the step prior to the formation of the quinonoid intermediate, possibly in orienting the pyridine ring of the cofactor, in order to facilitate effective proton abstraction.

The 12C(12C,n) reaction (Q=-2.6 MeV) is a potential neutron source for the weak s-process occurring in shell-carbon burning of massive stars. The uncertainty in this reaction rate limits our understanding of the production of elements in the range 60 < A < 110. Current stellar models must rely on the smooth extrapolation of a dubious statistical model calculation based on experimental data taken at energies well above the Gamow window which lies below 3.2 MeV. At Notre Dame, this reaction cross section has been measured in finer steps at energies above 3.5 MeV, while successful measurements down to 3.1 MeV have just recently been achieved. In addition, a new extrapolation based on measurements of the mirror system has been developed which predicts a number of low-energy resonances while accounting well for the high-energy resonances. An overview of this work along with the most recent results and astrophysical implications are presented.

The 12C+12C fusion reaction plays a crucial role during stellar evolution. The astrophysically important energy range spans from 1 MeV to 3 MeV. However, its cross section has not been determined with enough precision, despite numerous studies, due to the extremely low reaction cross sections and the large experimental background. To allow measurements of the 12C+12C fusion at astrophysical energies, we developed an efficient thick-target method using large-area silicon strip detectors. Further measurements at even lower energies will be performed using coincidences between a silicon-detector and a Ge-detector array, at the high-current accelerator under construction at the University of Notre Dame. Since the coincidence method does not allow obtaining information about the channels without gamma-ray emission, a solenoid spectrometer has been constructed for complementary measurements. Meanwhile, we are also investigating the 24Mg(α, α') reaction using the Grand Raiden Spectrometer at RCNP to search for potential resonances in the 12C+12C fusion reaction. Preliminary results from these measurements will be presented.

The elements between iron and strontium are largely produced by the weak s-process occurring in massive stars during the late stages of convective core He burning and the convective shell carbon burning with the primary source of neutrons coming from the reaction 22Ne(α,n)25Mg. However, shell carbon burning may produce hot enough temperatures to activate 12C(12C,n)23Mg as a significant neutron source. Few studies have been done on this reaction, and the extrapolation from experimental data down to the relevant astrophysical energies is uncertain. Recent studies performed at the Nuclear Science Laboratory of Notre Dame aim to improve the existing reaction data using new experimental techniques as well as provide a more reliable extrapolation to the low energies not accessible by experiment. Preliminary results will be presented and the astrophysical implications will be discussed.

An evaluation of the Federal Weatherization Assistance Program to determine the fuel savings for participants in Minnesota has been completed. The homes selected in this study were weatherized between April and October 1978. Therefore, a comparison of normalized fuel consumption for the 1976 to 1977 and 1977 to 1978 heating seasons was an appropriate measure of the fuel savings achieved. In addition, a control group was established to reflect fuel consumption changes resulting from the effect of other public energy awareness programs. The results indicate that the average energy savings was 13.43%. This was based on 59 sample group and 37 control group homes representing the population of all weatherized and non-weatherized low-income homes in the state, respectively. The conclusions of this study are: at an average fuel cost of $6 per million Btu, weatherization has been accomplished at a simple payback of 3.5 years; 90% of the weatherized homeowners have expressed varying degrees of positive satisfaction; behavioral changes (example, raising thermostats) are significant in offsetting potential weatherization savings; and the Retrotech Job Book, in its present form, has not been used effectively.

ACUTE mountain sickness and high altitude pulmonary oedema are two acute medical problems for troops in the Himalayan terrain who frequently shuttle between sea level and high altitudes (10,000–16,000 ft.). These two acute illnesses have some features in common: time lag (they rarely occur within 12 h of arrival at the altitude or 96 h after arrival), throbbing headache, muscular cramps and pulmonary congestion. We have studied the acute circulatory response to high altitude hypoxia and investigated the extent to which shifts in the circulating blood volumes, if any, could be related to the time lag and clinical features of these acute illnesses.