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Social influences, peer delinquency, and low self-control: An examination of time-varying and reciprocal effects on delinquency over adolescence
We examine an integrated dynamic model of social influences and internal controls on delinquency in adolescence. We assessed to what extent parental bonds, peer delinquency, and self-control were reciprocally related to delinquency throughout adolescence, and whether their effects were time varying. We applied cross-lagged panel models to analyze these relationships using three waves of data from a sample of Swiss youth at ages 13 to 17. Results suggest that self-control is a strong predictor for future delinquent behavior. Moreover, social influences affect self-control into adolescence, contributing to a growing area of research on the dynamic properties of self-control over the life course. Social influences, in particular peer delinquency, are also reciprocally related to delinquency, implying that delinquency can lead to cumulative disadvantages that further entrench individuals in antisocial pathways over the life course.</jats:p
Inside-Out Evacuation of Transitional Protoplanetary Disks by the Magneto-Rotational Instability
How do T Tauri disks accrete? The magneto-rotational instability (MRI)
supplies one means, but protoplanetary disk gas is typically too poorly ionized
to be magnetically active. Here we show that the MRI can, in fact, explain
observed accretion rates for the sub-class of T Tauri disks known as
transitional systems. Transitional disks are swept clean of dust inside rim
radii of ~10 AU. Stellar coronal X-rays ionize material in the disk rim,
activating the MRI there. Gas flows from the rim to the star, at a rate limited
by the depth to which X-rays ionize the rim wall. The wider the rim, the larger
the surface area that the rim wall exposes to X-rays, and the greater the
accretion rate. Interior to the rim, the MRI continues to transport gas; the
MRI is sustained even at the disk midplane by super-keV X-rays that Compton
scatter down from the disk surface. Accretion is therefore steady inside the
rim. Blown out by radiation pressure, dust largely fails to accrete with gas.
Contrary to what is usually assumed, ambipolar diffusion, not Ohmic
dissipation, limits how much gas is MRI-active. We infer values for the
transport parameter alpha on the order of 0.01 for GM Aur, TW Hyd, and DM Tau.
Because the MRI can only afflict a finite radial column of gas at the rim, disk
properties inside the rim are insensitive to those outside. Thus our picture
provides one robust setting for planet-disk interaction: a protoplanet interior
to the rim will interact with gas whose density, temperature, and transport
properties are definite and decoupled from uncertain initial conditions. Our
study also supplies half the answer to how disks dissipate: the inner disk
drains from the inside out by the MRI, while the outer disk photoevaporates by
stellar ultraviolet radiation.Comment: Accepted to Nature Physics June 7, 2007. The manuscript for
publication is embargoed per Nature policy. This arxiv.org version contains
more technical details and discussion, and is distributed with permission
from the editors. 10 pages, 4 figure
Reduced Exercise Tolerance and Pulmonary Capillary Recruitment with Remote Secondhand Smoke Exposure
RATIONALE: Flight attendants who worked on commercial aircraft before the smoking ban in flights (pre-ban FAs) were exposed to high levels of secondhand smoke (SHS). We previously showed never-smoking pre-ban FAs to have reduced diffusing capacity (Dco) at rest. METHODS: To determine whether pre-ban FAs increase their Dco and pulmonary blood flow (Qc) during exercise, we administered a symptom-limited supine-posture progressively increasing cycle exercise test to determine the maximum work (watts) and oxygen uptake (VO2) achieved by FAs. After 30 min rest, we then measured Dco and Qc at 20, 40, 60, and 80 percent of maximum observed work. RESULTS: The FAs with abnormal resting Dco achieved a lower level of maximum predicted work and VO2 compared to those with normal resting Dco (mean±SEM; 88.7±2.9 vs. 102.5±3.1%predicted VO2; p = 0.001). Exercise limitation was associated with the FAs' FEV(1) (r = 0.33; p = 0.003). The Dco increased less with exercise in those with abnormal resting Dco (mean±SEM: 1.36±0.16 vs. 1.90±0.16 ml/min/mmHg per 20% increase in predicted watts; p = 0.020), and amongst all FAs, the increase with exercise seemed to be incrementally lower in those with lower resting Dco. Exercise-induced increase in Qc was not different in the two groups. However, the FAs with abnormal resting Dco had less augmentation of their Dco with increase in Qc during exercise (mean±SEM: 0.93±0.06 vs. 1.47±0.09 ml/min/mmHg per L/min; p<0.0001). The Dco during exercise was inversely associated with years of exposure to SHS in those FAs with ≥10 years of pre-ban experience (r = -0.32; p = 0.032). CONCLUSIONS: This cohort of never-smoking FAs with SHS exposure showed exercise limitation based on their resting Dco. Those with lower resting Dco had reduced pulmonary capillary recruitment. Exposure to SHS in the aircraft cabin seemed to be a predictor for lower Dco during exercise
Splenectomy for solitary splenic metastasis of ovarian cancer
BACKGROUND: Splenic metastases occur in rare cases with a few case reports of patients in the literature. Generally, splenic metastases mean late dissemination of a disease. Solitary splenic metastases from solid tumors are extremely unusual. CASE PRESENTATION: We report a case of a patient with ovarian mucinous cystadenocarcinoma who underwent splenectomy for isolated parenchymal metastasis. CONCLUSION: Ovarian epithelial tumors comprised most of isolated splenic metastases from gynecologic tumor. When isolated splenic recurrence is suspected on image studies and serum tumor markers, intraabdominal gross findings should be examined to exclude peritoneal carcinomatosis. If only spleen was under suspicion of recurrence of ovarian cancer, splenectomy may play a therapeutic role
How can the practice nurse be more involved in the care of the chronically ill? The perspectives of GPs, patients and practice nurses
BACKGROUND: A well established "midlevel" of patient care, such as nurse practitioners and/or physician assistants, exits in many countries like the US, Canada, and Australia. In Germany, however there is only one kind of profession assisting the physician in practices, the practice nurse. Little is known about the present involvement of practice nurses in patients' care in Germany and about the attitudes of GPs, assistants and patients concerning an increased involvement. The aim of our study was to get qualitative information on the extent to which practice nurses are currently involved in the treatment of patients and about possibilities of increased involvement as well as on barriers of increased involvement. METHODS: We performed qualitative, semi-structured interviews with 20 GPs, 20 practice nurses and 20 patients in the Heidelberg area. The interviews were digitally recorded, transcribed and content-analysed with ATLAS.ti. RESULTS: Practice nurses are only marginally involved in the treatment of patients. GPs as well as patients were very sceptical about increased involvement in care. Patients were sceptical about nurses' professional background and feared a worsening of the patient doctor relationship. GPs also complained about the nurses' deficient education concerning medical knowledge. They feared a lack of time as well as a missing reimbursement for the efforts of an increased involvement. Practice nurses were mostly willing to be more involved, regarding it as an appreciation of their role. Important barriers were lack of time, overload with administrative work, and a lack of professional knowledge. CONCLUSION: Practice nurses were only little involved in patient care. GPs were more sceptical than patients regarding an increased involvement. One possible area, accepted by all interviewed groups, was patient education as for instance dietary counselling. New treatment approaches as the chronic care model will require a team approach which currently only marginally exists in the German health care system. Better medical education of practice nurses is indispensable, but GPs also have to accept that they cannot fulfil the requirement of future care alone
A search for the decay modes B+/- to h+/- tau l
We present a search for the lepton flavor violating decay modes B+/- to h+/-
tau l (h= K,pi; l= e,mu) using the BaBar data sample, which corresponds to 472
million BBbar pairs. The search uses events where one B meson is fully
reconstructed in one of several hadronic final states. Using the momenta of the
reconstructed B, h, and l candidates, we are able to fully determine the tau
four-momentum. The resulting tau candidate mass is our main discriminant
against combinatorial background. We see no evidence for B+/- to h+/- tau l
decays and set a 90% confidence level upper limit on each branching fraction at
the level of a few times 10^-5.Comment: 15 pages, 7 figures, submitted to Phys. Rev.
Evidence for an excess of B -> D(*) Tau Nu decays
Based on the full BaBar data sample, we report improved measurements of the
ratios R(D(*)) = B(B -> D(*) Tau Nu)/B(B -> D(*) l Nu), where l is either e or
mu. These ratios are sensitive to new physics contributions in the form of a
charged Higgs boson. We measure R(D) = 0.440 +- 0.058 +- 0.042 and R(D*) =
0.332 +- 0.024 +- 0.018, which exceed the Standard Model expectations by 2.0
sigma and 2.7 sigma, respectively. Taken together, our results disagree with
these expectations at the 3.4 sigma level. This excess cannot be explained by a
charged Higgs boson in the type II two-Higgs-doublet model. We also report the
observation of the decay B -> D Tau Nu, with a significance of 6.8 sigma.Comment: Expanded section on systematics, text corrections, improved the
format of Figure 2 and included the effect of the change of the Tau
polarization due to the charged Higg
Search for the decay modes D^0 → e^+e^-, D^0 → μ^+μ^-, and D^0 → e^±μ∓
We present searches for the rare decay modes D^0→e^+e^-, D^0→μ^+μ^-, and D^0→e^±μ^∓ in continuum e^+e^-→cc events recorded by the BABAR detector in a data sample that corresponds to an integrated luminosity of 468  fb^(-1). These decays are highly Glashow–Iliopoulos–Maiani suppressed but may be enhanced in several extensions of the standard model. Our observed event yields are consistent with the expected backgrounds. An excess is seen in the D^0→μ^+μ^- channel, although the observed yield is consistent with an upward background fluctuation at the 5% level. Using the Feldman–Cousins method, we set the following 90% confidence level intervals on the branching fractions: B(D^0→e^+e^-)<1.7×10^(-7), B(D^0→μ^+μ^-) within [0.6,8.1]×10^(-7), and B(D^0→e^±μ^∓)<3.3×10^(-7)
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