Evidence of Incoherent Carriers Associated with Resonant Impurity Levels and Their Influence on Superconductivity in the Anomalous Superconductor Pb_{1-x}Tl_{x}Te.

We present a combined experimental and theoretical study of the evolution of the Fermi surface of the anomalous superconductor Pb_{1-x}Tl_{x}Te as a function of thallium concentration, drawing on a combination of magnetotransport measurements (Shubnikov-de Haas oscillations and the Hall coefficient), angle resolved photoemission spectroscopy, and density functional theory calculations of the electronic structure. Our results indicate that for Tl concentrations beyond a critical value, the Fermi energy coincides with resonant impurity states in Pb_{1-x}Tl_{x}Te, and we rule out the presence of an additional valence band maximum at the Fermi energy. A comparison to nonsuperconducting Pb_{1-x}Na_{x}Te implies that the presence of these impurity states at the Fermi energy provides the enhanced pairing interaction and thus also the anomalously high temperature superconductivity in this material.

Scale-invariant magnetoresistance in a cuprate superconductor.

The anomalous metallic state in the high-temperature superconducting cuprates is masked by superconductivity near a quantum critical point. Applying high magnetic fields to suppress superconductivity has enabled detailed studies of the normal state, yet the direct effect of strong magnetic fields on the metallic state is poorly understood. We report the high-field magnetoresistance of thin-film La2-x Sr x CuO4 cuprate in the vicinity of the critical doping, 0.161 ≤ p ≤ 0.190. We find that the metallic state exposed by suppressing superconductivity is characterized by magnetoresistance that is linear in magnetic fields up to 80 tesla. The magnitude of the linear-in-field resistivity mirrors the magnitude and doping evolution of the well-known linear-in-temperature resistivity that has been associated with quantum criticality in high-temperature superconductors.

Giant suppression of phononic heat transport in a quantum magnet BiCu2PO6.

Thermal transport of quantum magnets has elucidated the nature of low energy elementary excitations and complex interplay between those excited states via strong scattering of thermal carriers. BiCu2PO6 is a unique frustrated spin-ladder compound exhibiting highly anisotropic spin excitations that contain both itinerant and localized dispersion characters along the b- and a-axes respectively. Here, we investigate thermal conductivity κ of BiCu2PO6 under high magnetic fields (H) of up to 30 tesla. A dip-feature in κ, located at ~15 K at zero-H along all crystallographic directions, moves gradually toward lower temperature (T) with increasing H, thus resulting in giant suppression by a factor of ~30 near the critical magnetic field of Hc ≅ 23.5 tesla. The giant H- and T-dependent suppression of κ can be explained by the combined result of resonant scattering of phononic heat carriers with magnetic energy levels and increased phonon scattering due to enhanced spin fluctuation at Hc, unequivocally revealing the existence of strong spin-phonon coupling. Moreover, we find an experimental indication that the remaining magnetic heat transport along the b-axis becomes almost gapless at the magnetic quantum critical point realized at Hc.

Unfolding the physics of URu2Si2 through silicon to phosphorus substitution.

The heavy fermion intermetallic compound URu2Si2 exhibits a hidden-order phase below the temperature of 17.5 K, which supports both anomalous metallic behavior and unconventional superconductivity. While these individual phenomena have been investigated in detail, it remains unclear how they are related to each other and to what extent uranium f-electron valence fluctuations influence each one. Here we use ligand site substituted URu2Si(2-x)P(x) to establish their evolution under electronic tuning. We find that while hidden order is monotonically suppressed and destroyed for x≤0.035, the superconducting strength evolves non-monotonically with a maximum near x≈0.01 and that superconductivity is destroyed near x≈0.028. This behavior reveals that hidden order depends strongly on tuning outside of the U f-electron shells. It also suggests that while hidden order provides an environment for superconductivity and anomalous metallic behavior, it's fluctuations may not be solely responsible for their progression.

Observation of universal strong orbital-dependent correlation effects in iron chalcogenides.

Establishing the appropriate theoretical framework for unconventional superconductivity in the iron-based materials requires correct understanding of both the electron correlation strength and the role of Fermi surfaces. This fundamental issue becomes especially relevant with the discovery of the iron chalcogenide superconductors. Here, we use angle-resolved photoemission spectroscopy to measure three representative iron chalcogenides, FeTe0.56Se0.44, monolayer FeSe grown on SrTiO3 and K0.76Fe1.72Se2. We show that these superconductors are all strongly correlated, with an orbital-selective strong renormalization in the dxy bands despite having drastically different Fermi surface topologies. Furthermore, raising temperature brings all three compounds from a metallic state to a phase where the dxy orbital loses all spectral weight while other orbitals remain itinerant. These observations establish that iron chalcogenides display universal orbital-selective strong correlations that are insensitive to the Fermi surface topology, and are close to an orbital-selective Mott phase, hence placing strong constraints for theoretical understanding of iron-based superconductors.

Adjuvant chemotherapy for bladder cancer-why does level 1 evidence not support it?

Neoadjuvant cisplatin-based combination chemotherapy provides a 5% increase in cure rate, an increase in median survival of about 3 years, and statistically significant and clinically relevant increments in overall survival for patients with invasive bladder cancer. Despite compelling level 1 data, it has become quite clear that facts that are similar to those that changed the paradigm of treatment of breast cancer in the 1970s have not had a similar influence on patterns of practice in bladder cancer care. Instead of using this proven approach, cystectomy alone or surgery followed by adjuvant chemotherapy is often used as a functional alternative for patients with deeply invasive and/or node-metastatic disease discovered at radical cystectomy. However, there is no well-powered level 1 evidence to support routine adjuvant chemotherapy for invasive bladder cancer, and some randomized trials have shown inferior outcomes. There is a clear need for a well-designed, randomized trial that tests the utility of adjuvant chemotherapy for invasive bladder cancer, but until that has been completed, neoadjuvant chemotherapy followed by definitive local treatment should be the standard of care for invasive bladder cancer.

Observation of temperature-induced crossover to an orbital-selective Mott phase in A(x)Fe(2-y)Se2 (A=K, Rb) superconductors.

Using angle-resolved photoemission spectroscopy, we observe the low-temperature state of the A(x)Fe(2-y)Se(2) (A=K, Rb) superconductors to exhibit an orbital-dependent renormalization of the bands near the Fermi level-the d(xy) bands heavily renormalized compared to the d(xz)/d(yz) bands. Upon raising the temperature to above 150 K, the system evolves into a state in which the d(xy) bands have depleted spectral weight while the d(xz)/d(yz) bands remain metallic. Combined with theoretical calculations, our observations can be consistently understood as a temperature-induced crossover from a metallic state at low temperatures to an orbital-selective Mott phase at high temperatures. Moreover, the fact that the superconducting state of A(x)Fe(2-y)Se(2) is near the boundary of such an orbital-selective Mott phase constrains the system to have sufficiently strong on-site Coulomb interactions and Hund's coupling, highlighting the nontrivial role of electron correlation in this family of iron-based superconductors.

Cost-free and sustainable incentive increases healthy eating decisions during elementary school lunch.

We aimed to develop a cost-free and sustainable program to influence healthier eating decisions during elementary school lunch. Baseline food and beverage choices were assessed for 9 days during lunch service at two racially and economically diverse elementary schools in Spartanburg County, SC, USA. After being informed that the labeled items on the daily lunch menu represented the healthiest choice, students were allowed to ring a call bell in the cafeteria for public recognition when they chose all of the identified healthiest food and beverage items during lunch service. Using menus matched to the baseline phase, food and beverage choices were measured during a 9-day intervention phase. After 30 days, food and beverage choices were reassessed during a 3-day follow-up phase. Healthiest food & beverage choices increased 49% with >60% of students choosing non-flavored milk over flavored milk during the intervention phase. There was no difference in the success of the program between the two schools. The program continued and healthy eating decisions were significantly sustained at a 30-day follow-up assessment. Public recognition through bell ringing appears to be an effective practice to sustain increases in healthy eating decisions during elementary school lunch and warrants expansion to larger scale, longitudinal trials.

Enhanced Fermi-surface nesting in superconducting BaFe2(As(1-x)P(x))2 revealed by the de Haas-van Alphen effect.

The three-dimensional Fermi-surface morphology of superconducting BaFe2(As0.37P0.63)2 with T(c)=9 K is determined using the de Haas-van Alphen effect. The inner electron pocket has a similar area and k(z) interplane warping to the observed hole pocket, revealing that the Fermi surfaces are geometrically well nested in the (π,π) direction. These results are in stark contrast to the fermiology of the nonsuperconducting phosphides (x=1), and therefore suggest an important role for nesting in pnictide superconductivity.

Cutaneous pythiosis in a nestling white-faced ibis.

A nestling white-faced ibis (Plegadis chihi) with multifocal skin ulcerations on the wings, neck, head, and limbs was found in a wetland agricultural region of the central valley in California. Pathologic, microbiologic, and molecular findings were consistent with restricted, cutaneous infection by the oomycete Pythium insidiosum. The microscopic features of the disease, including intense, necrotizing eosinophilic and granulomatous inflammation, are similar to those previously described in mammals. Pythiosis, which is most typical in tropical and subtropical climates, has recently emerged in California as a cause of cutaneous and enteric disease in horses and dogs, respectively. Environmental stability and persistence of a "water-mold" in the arid central valley of California could be associated with agricultural and community watering practices. To the best of the authors' knowledge, this is the first published report of pythiosis in birds.

Exploring opportunities for collaboration between the corporate sector and the dental education community.

The ultimate purpose of both dental industry and dental education is to improve the oral health of the public. This report provides background information on the different roles and objectives of the dental industry and dental education communities, the different operating environment of each sector and also areas of common interest where collaboration will be of mutual benefit. The report addresses five areas for potential collaboration between the dental industry and the dental education communities: 1. Contribution to joint activities. 2. Effectiveness and efficiency. 3. Workforce needs. 4. Middle- and low-income countries. 5. The future of International Federation of Dental Educators and Associations (IFDEA). The traditional areas of support and their limitations that have been provided by industry are outlined in the report and some new approaches for collaboration are considered. Industry-based research has been an important factor in developing new products and technologies and in promoting oral health. However there is a need to facilitate the introduction of these developments at an early stage in the education process. Industry has to operate in an efficient manner to remain competitive and maximise its returns and therefore survive. The academic sector operates in a different environment and under different governance structures; although some trends are noted towards adoption of greater efficiency and financial accountability similar to industry. Opportunities to jointly develop best business practices should be explored. Industry has responded well to the oral health needs of the public through the development of new products and technologies. The education community needs to respond in a similar way by examining different healthcare delivery models worldwide and developing programmes to train members of the dental team to cater for future needs and demands of communities in different regions of the world. The reputation of industry-based scientists and clinicians is high, and their role in contributing to the dental education process in practical ways needs to be explored and further developed. Closer relationships between industry scientists and faculty and students could assist industrys need and desire to develop new technologies for the broader dental care system. The corporate sector can play a key role in the future success of IFDEA by providing support and expertise in developing areas such as regional leadership institutes, a Global Faculty and Network and in collaborating in developing continuing education programmes as well as involvement in its governance. Thirteen recommendations are made in the report. These are considered to be important initial steps in developing the already strong relationship between the education and corporate sectors. Partnership and collaborating more effectively along the lines suggested should, almost certainly, generate mutually beneficial outcomes, whilst serving over the long term to elevate the publics oral health status on a global basis.

A comparison of modelling and imagery in the acquisition and retention of motor skills.

Although many researchers have examined the effects of imagery and/or modelling interventions, it is unclear which of the two interventions is more effective. In two experiments, novice learners assessed over multiple trials of a free weight squat lifting or a stabilometer balancing task were given modelling, imagery, a combination of modelling and imagery, or control interventions. Group differences indicated, in general, that groups receiving modelling (modelling, combination) evidenced a more appropriate form than groups that did not receive modelling (imagery, control). When apparent, these differences were already in place after the first of several interventions. Practical implications are that even a single bout of modelling can have immediate beneficial effects on movement form (Experiments 1 and 2) and outcome (Experiment 1).

Antibodies against human putamen in adolescents with anorexia nervosa.

OBJECTIVE: To examine whether antiputamen antibodies are present in adolescents with anorexia nervosa (AN). METHOD: Using enzyme-linked immunosorbent assay (ELISA) with an extract of human putamen as an antigen, sera samples obtained from 22 adolescents with active AN and from 22 healthy adolescents (control group) were assayed for antibodies to neuronal components RESULTS: Mean optical density (OD) readings for serum antibodies against human putamen in adolescents with AN was significantly greater than the mean OD readings in the control group (0.492 +/- 0.086 vs. 0.275 +/- 0.028, p =.02). When serum positivity was defined as an OD level greater than 2 SD above the mean control group value (0.541), antiputamen antibodies were detected in the blood of 6 AN patients (27%) whereas they were detected in the blood of 1 patient (5%) in the control group (p <.05; Fisher's exact test). DISCUSSION: The detection of antiputamen antibodies in adolescents with AN suggests an underlying immune process at the putamen level in some patients with this eating disorder.

Omega-3 polyunsaturated fatty acids in adolescents: knowledge and consumption.

OBJECTIVE: To assess adolescents' knowledge about n-3 polyunsaturated fatty acids (PUFA) and their dietary intake of these important nutrients. METHODS: A questionnaire consisting of 12 questions assessing the knowledge and intake of n-3 PUFA and of a 24-h dietary recall was administered to 1117 ninth-grade adolescents (52% girls and 48% boys) attending five public schools. The adolescents were subsequently provided with verbal and written information on the health benefits, requirements, and dietary sources of n-3 PUFA. Dietary recalls were analyzed for energy and n-3 PUFA intake. Descriptive statistics, Student's t-tests, Chi-square analysis, and multiple regression analysis were used to assess adolescents' knowledge about n-3 PUFA as well as to examine relationships of independent variables with n-3 PUFA intake. RESULTS: Most adolescents (89%) believed that eating fish, a main source of very long chain (VLC) n-3 PUFA, is healthy and may prevent heart disease (59%), but only a few knew about n-3 PUFA's role in alleviating inflammation (29%) and its potential for cancer prevention (25%). Many were aware of marine sources of n-3 PUFA, such as salmon (67%), tuna (46%), mackerel (30%), and herring (26%), but only 36% knew about adequate intake of VLC n-3 PUFA. The main source of n-3 PUFA information was parents (58%), whereas only 21% of adolescents reported that their care providers had discussed health benefits of n-3 PUFA with them. About one-third of adolescents consumed fish at least once a week, and 29% consumed fish once a month. Dislike (22% of participants) and allergy (3%) were the main reasons for rarely (< or = 3 times/year; 18%) or never (17%) consuming fish. Only one adolescent reported daily consumption of a fish concentrate supplement. Daily consumption of linolenic acid was higher in boys (0.38 +/- 0.02 g) than in girls (0.31 +/- 0.01 g; p =.002). Total intake of n-3 PUFA represented only 30% of the presently available (Canadian) recommended daily allowance (CRDA) for 14- to 15-year-old boys (1.4 g/day) and 29% of the CRDA for 14- to 15-year-old girls (1.2 g/day). CONCLUSIONS: Adolescents are aware of some of the health benefits of n-3 PUFA but lack concrete information about dietary requirements of n-3 PUFA and about n-3 PUFA content of various dietary sources.

Serotesting versus presumptive varicella vaccination of adolescents with a negative or uncertain history of chickenpox.

OBJECTIVE: To review the current practice of adolescent health care providers when an adolescent reports a negative or uncertain history of chickenpox in order to provide information for future practice. METHODS: Retrospective chart review of a sample of patients seen in a hospital-based adolescent primary care clinic between 1996 and 1999. RESULTS: Among adolescents who reported a positive history of chickenpox (190 patients, aged 15 +/- 1 years), varicella occurred before age 5 years in 30%, between 5 and 10 years in 56%, and at older than age 10 years in 14% of the patients. When adolescents reported a negative or uncertain history of varicella (55 patients, aged 15 +/- 1 years), serotesting was ordered for the majority (73%) of cases, while only 16% were presumptively vaccinated with varicella vaccine. In six patients no intervention was noted in the charts, and these patients were contacted. In 80% of the patients who were serotested, varicella IgG titers of > or = 1:32 indicated a previous unnoticed infection and lifelong immunity to varicella. In only 20% of the patients sera were negative for varicella IgG titer, requiring varicella vaccination. There was no statistical difference between the number of siblings of patients with a positive serologic test (3 +/- 1) and the number of siblings of seronegative patients (2 +/- 1, p = 0.41). Seven of the eight seronegative patients consented to varicella vaccination and were vaccinated within 10 months of serotesting. CONCLUSIONS: These data support the practice of serotesting for a previously unnoticed varicella infection rather than presumptive vaccination in the adolescent age group. A follow-up vaccination of seronegative adolescents should be scheduled as close to serotesting as possible.

Urinary leukotriene (LT) E(4) in adolescents with dysmenorrhea: a pilot study.

In the present study we measured levels of urinary leukotriene (LT) E(4) as an index of LT production during the menstrual cycle in adolescents. Mean urinary LTE(4) levels in girls with dysmenorrhea was approximately threefold higher than normal laboratory values on Day 1 of the menstrual period and approximately twofold higher than normal laboratory values on Day 5 of the menstrual period. Compared with urinary LTE(4) levels in girls with eumenorrhea, urinary LTE(4) levels in girls with dysmenorrhea were higher on Day 1 [361 +/- 123 pg/mg creatinine vs. 122 +/- 37 pg/mg creatinine, p =.1; not significant (NS)] and on Day 5 (202 +/- 26 pg/mg creatinine vs. 117 +/- 26 pg/mg creatinine, p <.05) of the menstrual period, as well as on Day 10 (159 +/- 33 pg/mg creatinine vs. 88 +/- 21 pg/mg creatinine, p =.1; NS) of the menstrual cycle. Increased urinary excretion of leukotrienes, inflammatory mediators known to cause potent vasoconstriction and uterine contractions, in girls with dysmenorrhea in this pilot study, suggests that these mediators may be involved in generating dysmenorrhea symptoms in adolescents.

Mutations in the cardiac transcription factor NKX2.5 affect diverse cardiac developmental pathways.

Heterozygous mutations in NKX2.5, a homeobox transcription factor, were reported to cause secundum atrial septal defects and result in atrioventricular (AV) conduction block during postnatal life. To further characterize the role of NKX2.5 in cardiac morphogenesis, we sought additional mutations in groups of probands with cardiac anomalies and first-degree AV block, idiopathic AV block, or tetralogy of Fallot. We identified 7 novel mutations by sequence analysis of the NKX2.5-coding region in 26 individuals. Associated phenotypes included AV block, which was the primary manifestation of cardiac disease in nearly a quarter of affected individuals, as well as atrial septal defect and ventricular septal defect. Ventricular septal defect was associated with tetralogy of Fallot or double-outlet right ventricle in 3 individuals. Ebstein's anomaly and other tricuspid valve abnormalities were also present. Mutations in human NKX2.5 cause a variety of cardiac anomalies and may account for a clinically significant portion of tetralogy of Fallot and idiopathic AV block. The coinheritance of NKX2.5 mutations with various congenital heart defects suggests that this transcription factor contributes to diverse cardiac developmental pathways.

Surgery-associated factor VIII inhibitors in patients without hemophilia.

The acquisition of antibodies to factor VIII (ie, factor VIII protein) by patients without hemophilia is associated with conditions such as pregnancy, lymphoma, and autoimmune disorders. We present three patients who acquired factor VIII antibodies in the postoperative setting. Preoperatively, none gave a history of bleeding even with past surgeries and all had normal coagulation tests. Within days of surgery (bowel resection, cholecystectomy, coronary bypass), a bleeding diathesis emerged with prolonged partial thromboplastin time, decreased factor VIII levels, and demonstrable factor VIII antibodies. All patients required multiple blood transfusions and urgent reexploration for hemostatic control. All were treated with high dose human factor VIII infusions, corticosteroids, and various forms of immunosuppression. We wish to raise awareness of surgery as a precipitating cause of acquired hemophilia, which is something to be considered with unusual postoperative bleeding. This syndrome is remarkable for its abrupt onset within days of surgery, dramatic bleeding, subsequent persistence, but potential reversal by immunosuppression.

Linked insurance-tumor registry database for health services research.

OBJECTIVE: Breast cancer screening and treatment data are often limited to restricted populations, including women older than 65 years old. The goal of this project was to develop procedures to link tumor registry and insurance claims databases on women younger than 65 years old with breast cancer and to assess the accuracy and validity of the linked dataset. METHODS: Iowa Cancer Registry (ICR) and Wellmark Blue Cross/Blue Shield of Iowa (BC/BS) membership files of women with incident in situ or invasive breast cancer from 1989 to 1996 were linked. An automated deterministic match was followed with visual inspection from three independent reviewers applying a matching protocol. Matched and overall registry data were compared to assess population representativeness. Claims from BC/BS for incident cases during 1994 were examined for coding of a recent breast cancer diagnosis or treatment. RESULTS: The final dataset included 4,397 matched cases of patients aged 21 years and older from 1989 to 1996. The sociodemographic and tumor characteristics of the ICR population younger than 65 years old (n = 7,469) with breast cancer or carcinoma in situ were nearly identical with those of the matched patients younger than 65 years old (n = 3,449). Nearly all (96%) of the 445 matched incident cases in 1994 had claims data (CPT, DRG, or ICD-9 code) indicative of breast cancer. Treatment patterns varied by data source, with agreement ranging from 76% to 82%. CONCLUSIONS: The validity and generalizability of these data demonstrate their potential for further health services research among younger insured women with breast cancer. Additionally, the process outlined may be useful for developing other datasets to study other cancers in the population younger than 65 years old.