Distinct spin and orbital dynamics in Sr2RuO4.

The unconventional superconductor Sr2RuO4 has long served as a benchmark for theories of correlated-electron materials. The determination of the superconducting pairing mechanism requires detailed experimental information on collective bosonic excitations as potential mediators of Cooper pairing. We have used Ru L3-edge resonant inelastic x-ray scattering to obtain comprehensive maps of the electronic excitations of Sr2RuO4 over the entire Brillouin zone. We observe multiple branches of dispersive spin and orbital excitations associated with distinctly different energy scales. The spin and orbital dynamical response functions calculated within the dynamical mean-field theory are in excellent agreement with the experimental data. Our results highlight the Hund metal nature of Sr2RuO4 and provide key information for the understanding of its unconventional superconductivity.

A Comparative Analysis of Teaching and Evaluation Methods in Nurse Practitioner Education Programs in Australia, Canada, Finland, Norway, the Netherlands and USA.

A scoping review of published literature and dialogue with international nurse practitioner educators and researchers revealed the education of nurse practitioner students varied within and between countries. This lack of cohesiveness hinders nurse practitioner role development and practice nationally and internationally. A rapid review of grey literature was conducted on nurse practitioner education standards in six countries (Australia, Canada, Finland, Norway, the Netherlands, and USA). Data were extracted from graduate level nurse practitioner education programs' websites from each country (n = 24). Extracted data were verified for accuracy and completeness with a nurse practitioner educator from each program. Data were analyzed using content analysis. Variations in nurse practitioner education within and between countries were explored by comparing admission criteria, curricular content, clinical requirements, teaching methods, and assignment and evaluative methods. The findings will help inform education programs and further research about nurse practitioner education internationally.

Erratum: Ultrafast Doublon Dynamics in Photoexcited 1T-TaS_{2} [Phys. Rev. Lett. 120, 166401 (2018)].

This corrects the article DOI: 10.1103/PhysRevLett.120.166401.

Ultrafast Doublon Dynamics in Photoexcited 1T-TaS_{2}.

Strongly correlated materials exhibit intriguing properties caused by intertwined microscopic interactions that are hard to disentangle in equilibrium. Employing nonequilibrium time-resolved photoemission spectroscopy on the quasi-two-dimensional transition-metal dichalcogenide 1T-TaS_{2}, we identify a spectroscopic signature of doubly occupied sites (doublons) that reflects fundamental Mott physics. Doublon-hole recombination is estimated to occur on timescales of electronic hopping ℏ/J≈14 fs. Despite strong electron-phonon coupling, the dynamics can be explained by purely electronic effects captured by the single-band Hubbard model under the assumption of weak hole doping, in agreement with our static sample characterization. This sensitive interplay of static doping and vicinity to the metal-insulator transition suggests a way to modify doublon relaxation on the few-femtosecond timescale.

Kangaroo mother care in the neonatal intensive care unit: staff attitudes and beliefs and opportunities for parents.

AIM: To compare attitudes towards Kangaroo mother care (KMC) among staff in two high-tech neonatal intensive care units, which provided parents with different opportunities to get involved in their infants' care. METHOD: Questionnaires were completed by healthcare staff in Unit A, which provided parents with unrestricted access so that they could provide continuous KMC, and Unit B, where parents could only practice KMC intermittently. RESULTS: Unit A staff were more positive about the benefits and use of KMC, including its use in unstable infants, and rated their knowledge and practical skills more highly than staff in the other unit. Unit B staff also appreciated the method, but expressed more hesitation in using it with unstable infants. In particular, they stressed the need to adapt the physical environment of the NICU to enable parents to stay with their infants and practice the method. CONCLUSION: Staff working in the NICU that gave parents unrestricted access were more positive about KMC than staff in the NICU that offered limited opportunities for parents to stay with their children. This finding suggests that it is important to eliminate unjustifiable obstacles to the presence of parents in the NICU, so that they can provide KMC.

Pattern of HIV viraemia and CD4 levels in relation to pregnancy in HIV-1 infected women.

The objective was to study HIV-1 viraemia and CD4 levels during and 6 months after pregnancy. HIV cultures on peripheral blood mononuclear cells (PBMC) and plasma from 225 samples were performed in 90 HIV-1 infected women with 59 continued and 35 terminated pregnancies. P-24 antigen and HIV-DNA were also studied. 34 women originated from European, 44 from African and 10 from other countries while 2 were of unknown origin. HIV was detected in 30% of the plasma cultures from the first trimester and in approximately 50% thereafter. Repeated plasma isolations did not give an indication of HIV activation, nor did the cross-sectional time-to-culture positivity in plasma and in PBMC, PBMC isolation frequencies, HIV-DNA and CD4 levels. The plasma viraemia frequencies were generally higher and the CD4 levels lower in the African women than in the European ones. Six months after delivery there was a significant decrease in the CD4 cell counts compared to delivery, but not when compared to the values during the first or second trimesters. The results showed that HIV activity during pregnancy was relatively stable, followed by indications of resumed activity during the first 6 months after delivery.

Phospholipid peroxidation after 60 min of global ischaemia and 10 min of reperfusion. A study in the isolated rat heart.

Peroxidation of polyunsaturated fatty acids in cell membranes is thought to be a crucial factor in the cascade leading to reperfusion damage in the myocardium. However, some studies also describe increased lipid peroxidation in ischaemic tissue. The present study therefore examines phospholipid peroxidation after 60 min of global ischaemia and during the initial phase of reperfusion in isolated Langendorff-perfused rat hearts. Lipids were extracted from these hearts and separated into phospholipid, triglyceride and non-esterified fatty acid fractions. The phospholipid fraction was hydrolysed with phospholipase A2, and reverse-phase high performance liquid chromatography of the fatty acids derived from the phospholipids was performed. Peroxidized polyunsaturated fatty acids were separated from unchanged fatty acids and amounts of monohydroxy or monohydroperoxy isomers were quantified by measuring conjugated dienes by UV absorption (235 nm). Phospholipids from ischaemic as well as free-radical-exposed tissue contained increased levels of peroxidized polyunsaturated fatty acids (20.7 +/- 2.4 and 20.5 +/- 2.3 respectively, v 11.8 +/- 1.4 units/mg dry weight in controls). After 2-10 min of reperfusion, a significant increase in phospholipid peroxidation was no longer detected (12.5 +/- 1.2 units/mg). The amount and the composition of non-esterified fatty acids were examined by gas chromatography. Ischaemia significantly increased both the amount of non-esterified fatty acids (1.5 +/- 0.8 v 4.9 +/- 1.8 nmol/mg dry wt) as well as the percentage composed of arachidonic acid (3.4 +/- 3.2% v 7.4 +/- 1.4%). Fatty acid levels remained elevated during reperfusion (5.5 +/- 1.9 nmol/mg and 7.0 +/- 1.4%). In conclusion, our results have demonstrated that prolonged ischaemia alone caused phospholipid peroxidation as well as accumulation of non-esterified arachidonic acid. There was no sign of further phospholipid peroxidation during reperfusion.

Measurements of leukotrienes in human plasma by solid phase extraction and high performance liquid chromatography.

Leukotrienes (LTs) are biologically active compounds derived from lipoxygenase catalyzed metabolism of arachidonic acid in mammalian tissues. The present report describes a simple method for extraction and isolation of dihydroxy-LTs; LTB4, LTB5 and the peptido-LTs; LTC4, LTD4 and LTE4 from human plasma, using a pretreatment cartridge which utilizes both hydrophobic and ion-exchange interactions. 5 ml acidified plasma or acetate buffer containing commercially available LT standards were passed through the cartridges under suction, and the absorbed LTs were subsequently eluted in a stepwise manner with acetate buffer containing increasing amounts of methanol. The eluted LTs were analyzed by reversed-phase high performance liquid chromatography (HPLC) on octadecylsilyl (ODS)-silica, using a Waters HPLC unit. Both with plasma and acetate buffer the present methodology resulted in good separation of the LTs with a total run-time of less than 32 min. Recovery of dihydroxy-LTs was approximately 80% (range 73-82%) both when the standards were dissolved in plasma and in acetate buffer. Recovery of the peptido-LTs was, however somewhat lower (47-50%). It should be noted that the present method has the advantage that exposure to chemicals of high toxicity is avoided.

Increased capillary permeability for plasma proteins in oral contraceptive users.

The transcapillary fluid balance was examined in eleven women before administration of a monophasic oral contraceptive (desogestrel 0.15 mg, ethinylestradiol 0.03 mg), and after three and six months of use. The interstitial colloid osmotic pressure was measured by the "wick" method, and the interstitial hydrostatic pressure by the "wick-in-needle" method in subcutaneous tissue on thorax and leg. During the six-month observation period, the following changes were observed: Plasma colloid osmotic pressure decreased (mean 1.8 mmHg, p = 0.047), as well as serum albumin (mean 5.1 g/l, p = 0.0006), total protein concentration (mean 2.8 g/l, p = 0.0006), hemoglobin (mean 0.5 g/dl, p = 0.014) and hematocrit (mean 1.8%, p = 0.047). Blood pressure and body weight remained unchanged, but foot volume showed a significant increase. The colloid osmotic pressure gradient (plasma-interstitium) was significantly reduced. The results indicate an increase in plasma volume in addition to an increased capillary permeability to plasma proteins during oral contraceptive use. We suggest that the observed changes in transcapillary fluid balance is caused by the estrogen component of the oral contraceptive pill.

PIP: Physicians at the University of Tromso in Norway enrolled 11 18-26 year old women in a study to determine the effects of 3 and 6 month low dose oral contraceptives (OC) use on transcapillary fluid dynamics. They measured interstitial fluid colloid osmotic pressure (COPi) of the subcutaneous tissue of the thorax and leg with the wick in needle method. A significant fall in hemoglobin (mean 0.7 g/dl) occurred between 0-3 months of OC use (p=.013) as well as in hematocrit (mean 2.3%, p=.044), serum albumin concentration (mean 4.5g/dl, p=.0028), and serum protein concentration (mean 3.2 g/dl, p=.0083). In addition, foot volume rose on average 92.5 ml (p=.002), but body weight and blood pressure stayed the same. Plasma colloid osmotic pressure (COPp) fell slightly (mean 1.1 mm Hg, p=.08). The COPi and interstitial fluid hydrostatic pressure (Pi) on the thorax and the leg did not change. No further changes in hemoglobin, hematocrit, serum albumin, serum protein concentration, COPp, and foot volume occurred during the last 3 months. During the entire 6 months, the transcapillary colloid osmotic pressure gradient on the leg fell on average 2.7 mm Hg (p=.004). It also fell on the thorax (mean 2 mm Hg) but the decrease was not significant. Between 3-6 months, a significant negative relationship between the change in foot volume and the COPi on the thorax occurred as was the change in serum protein (p=.0021). In fact, the change in serum protein was also negatively correlated with the COPi on the leg (p=.0127). Further the change in serum albumin between 3-6 months was positively correlated with the COPi on the leg (p=.0018). In addition, changes in serum protein were positively associated with the COPp (p=.0465). The researchers believed that the estrogen in the low dose OC induced the changes in transcapillary fluid balance.

Dose-dependent induction of ornithine decarboxylase and S-adenosyl-methionine decarboxylase activity by testosterone in the accessory sex organs of male rats.

The dose-dependent induction of ornithine decarboxylase (ODC) and adenosylmethionine decarboxylase (AMDC) activity in the different lobes of the prostate and the seminal vesicles (SV), 24 hours after administration of testosterone to castrated Wistar rats, has been studied. ODC and AMDC activities were low in all lobes 10 days after castration. A dose of approximately 300 micrograms testosterone/100 g body weight (B.W.) gave an ODC activity of 50 percent of maximum response, and at 600 micrograms/100 g B.W. maximum activity was reached in all the prostatic lobes and the SV. In the lateral and dorsal prostate, and the coagulating gland, the dose of testosterone giving 50% of maximum AMDC activity was reached after administration of between 450 and 600 micrograms/100 g B.W. In the ventral prostate and SV, the dose giving a 50% response was approximately 700 micrograms/100 g B.W. In conclusion, all prostatic lobes showed a clear dose-response relationship concerning the activity of ODC and AMDC following administration of different doses of testosterone. We have found minor differences in androgen responsiveness between the lobes when looking at the dose requirements for induction of AMDC activity. The dose-response curves could possibly be useful as a rapid in vivo bioassay for compounds with anti-androgenic properties in the prostate.

Ornithine decarboxylase and S-adenosylmethionine decarboxylase activity in the accessory sex organs of intact, castrated, and androgen-stimulated castrated rats.

We have studied the activities of ornithine decarboxylase and adenosylmethionine decarboxylase in the 10(6)-m/s2 supernatants of the different lobes of the prostate and the seminal vesicles of castrates, androgen-stimulated castrates, and intact controls. After castration L-ornithine decarboxylase (ODC) and S-adenosyl-L-methionine decarboxylase (AMDC) activities fell in all tissues examined. The induction of kinetics was followed for 72 h after administration of testosterone propionate to castrated rats. AMDC activities increased more rapidly than ODC activities in every tissue studied. Peak activities were reached more rapidly in the dorsal lobe than in the other tissues. ODC activity of the ventral lobe increased linearly for 48 h after stimulation. In the other tissues studied, ODC activity reached a maximum after 24 h and thereafter leveled off or decreased. In conclusion we have found distinct differences in ODC and AMDC activity in various tissues and major differences between treatment groups, with near extinction of activity at castration. In castrates stimulated with testosterone, the between-group differences prevailed but with different patterns of ODC versus AMDC activity. AMDC is seemingly rate-limiting in polyamine synthesis in stimulated tissues, while ODC controls synthesis in tissues from castrated rats.

The Hospital Capitation Payment Project: new incentives and tools for cost containment.

Blue Cross of North Dakota, Blue Cross of Massachusetts, and the Blue Cross and Blue Shield Association, along with 10 hospitals, developed and implemented the Hospital Capitation Payment Project as a novel approach for containing escalating hospital costs. The hospital is paid a prospective, fixed amount for each person covered; in exchange, it assumes responsibility to provide or pay for all covered services needed by that individual. This responsibility extends to payment for covered care provided by other hospitals. The new tools and incentives created by the program, notably an innovative management information system, are designed to help hospitals better manage the health care needs and related costs of a defined population.