Suppression of the critical temperature of superconducting NdFeAs(OF) single crystals by Kondo-like defect sites induced by alpha-particle irradiation

We report the effect of alpha-particle irradiation on the reduction of the critical temperature T{c} of a NdFeAs(OF) single crystal. Our data indicate that irradiation defects cause both nonmagnetic and magnetic scattering, resulting in the Kondo-like excess resistance Delta rho(T) proportional to lnT over 2 decades in temperatures above T{c}. The critical density of magnetic irradiation defects which suppresses T{c} is found to be much higher than those for cuprates and multiband BCS superconductors. We suggest that such anomalously weak pair breaking by irradiation defects indicates that magnetic scattering in pnictides is coupled with pairing interactions mediated by spin fluctuations.

[Transient visual loss: a practical approach]

Transient vision loss results from a variety of disorders including benign dry eye as well as vision- or life-threatening disorders such as giant cell arteritis. The goal of the initial evaluation is to determine the most likely mechanism based on the past medical history, characteristics of visual loss, and ophthalmologic and neurologic examinations. The ophthalmologist is often the first physician consulted and plays an essential role. Indeed, identification of the mechanism of transient visual loss allows the care-taker to properly decide on the work-up, its timing (emergency or otherwise), and subsequent treatment.

Zn(5)Sb(4)In(2-delta) - a ternary derivative of thermoelectric zinc antimonides

Zn(5)Sb(4)In(2-delta) (delta = 0.15(3)) was synthesized in the form of millimeter-sized crystals from reaction mixtures containing excess zinc. The ternary intermetallic compound is temperature polymorphic, and at room temperature it crystallizes with a new structure type in the orthorhombic space group Pbcn, where a = 7.1619(2), b = 17.1562(4), c = 8.6887(4) A, V = 1067.6(1) A(3), and Z = 4. The structure features 3(2)434 nets of Sb atoms that are stacked in antiposition to yield layers of square antiprisms sharing edges plus intervening tetracapped tetrahedra (tetreadersterns). The majority of Zn atoms occupy peripheral tetrahedra of such tetraedersterns, and attain at the same time the peculiar five-coordination by one like atom and four Sb atoms typical for the structures of binary zinc antimonides. The In and remaining Zn atoms are distributed in the tetragonal channels formed by the square antiprisms and display some disorder. At temperatures below 200 K Zn(5)Sb(4)In(2-delta) undergoes a phase transition into a more ordered structure with monoclinic symmetry (P2(1)/c) without any change of the unit cell. The thermoelectric properties of Zn(5)Sb(4)In(2-delta) were measured between 10 and 350 K. Exceptionally low thermal conductivity values (1 W/mK range) were obtained in the whole temperature range. Resistivity and thermopower values are characteristic of a heavily doped or degenerate semiconductor (2.5 mOmega cm and 160 muV/K, respectively, at room temperature) and show a discontinuity around 220 K. The thermoelectric figure of merit of Zn(5)Sb(4)In(2-delta) is higher than that of Zn(4)Sb(3) in the investigated temperature range.

Impact of tumor size on survival in stage IB (T2N0M0) non-small cell lung cancer (NSCLC)

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Background: Patients with stage IB NSCLC have a relatively poor survival of ∼60% despite adequate surgical resection. The role of adjuvant chemotherapy in this disease remains controversial since the results of the IALT, JBR.10, ANITA and CALGB 9633 trials. It is important to risk stratify patients with Stage IB NSCLC and to offer adjuvant therapies to those at greatest risk for recurrence. Methods: We conducted a retrospective review of 216 consecutive, surgically treated patients with stage IB NSCLC. None of the patients received adjuvant chemotherapy. We studied the association of various clinical factors as well as tumor size and visceral pleural invasion upon tumor recurrence, disease free survival (DFS) and overall survival (OS) at 5 years. Results: Of 216 patients, 135 (62%) were male, 97 (45%) had adenocarcinoma, 115 (53%) had poorly differentiated tumors and the majority (88%) were treated with lobectomy. Visceral pleural invasion was noted in 37 (17%) patients. The 5 year OS and DFS rates were 59% and 54% respectively. Tumor size was = 4cm in 120 (56%) patients, 4.1–5 cm and >5cm in 48 (22%) patients each. The 5 year DFS was 40% and 58% for tumors > 5cm and = 5 cm respectively (p < 0.01). The 5 year OS was 49% and 61% respectively for tumors > 5cm and = 5cm. Pleural invasion was a predictor for DFS in the univariate analysis (p < 0.01) but not for OS. In the multivariable analysis, tumor size = 5cm was the only independent predictor of improved DFS (HR 0.46, C.I. 0.25–.84) and OS (HR=0.43, C.I. 0.23–0.80). Age, gender, histology, differentiation and visceral pleural invasion did not impact upon survival. Conclusions: In stage IB NSCLC, tumors > 5cm in diameter have a significantly worse prognosis. These findings if confirmed in other large series, make a case for subdividing Stage IB NSCLC. Tumor size appears to be the most important factor in risk stratification for patients with stage IB NSCLC. Hence patients with large tumors should be offered adjuvant therapy.

No significant financial relationships to disclose.

Conservative non-pharmacological treatment options are not frequently used in the management of hip osteoarthritis

Osteoarthritis (OA) is the most frequent joint disorder in seniors. Systematic reviews suggest that conservative treatment is effective and preferred in mild-moderate cases. The objective of this study was to examine the proportion of patients receiving physiotherapy, exercise or walking aids, and to explore factors associated with their prescription. We conducted a retrospective survey of patients about to undergo total hip arthroplasty for hip osteoarthritis. Patients were asked about past prescriptions for cane use, physiotherapy and exercise. Of 161 patients (36.6% male, mean age 68.7+/-10.1 years), 76% were prescribed a cane (adherence=86.2%). The main reason for not using a cane was vanity. Of the 28.0% patients prescribed physiotherapy, 73.3% received exercises compared to only 2.6% of non-physiotherapy patients. Patients who were older or worked in manual labour were more likely to be prescribed a cane and less likely to be prescribed physiotherapy or exercises. Men were less likely than women to be prescribed all three, but only cane use was statistically significant across genders. In conclusion, physiotherapy and exercise are not commonly prescribed in patients with hip OA.

Inorganic dust exposure causes pulmonary fibrosis in smokers: analysis using light microscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy

Smoking is alleged to cause pulmonary fibrosis, but the role of inorganic dust particulates has not been adequately examined. The authors hypothesize that inorganic dust exposure is an independent risk factor for the development of fibrosis in smokers. They studied a prospective series of 34 subjects with open lung biopsies, 18 of whom had adequate lung parenchyma for evaluation. They also examined the relationships between smoking (pack-years), respiratory bronchiolitis (RB), inorganic dusts, and interstitial fibrosis. They graded RB, fibrosis, and particulate dust by means of light microscopy. They performed a semiquantitative analysis of dust burden by using scanning electron microscopy with energy-dispersive X-ray spectroscopy. A logistic regression analysis demonstrated a significant association between smoking and RB (p = .03), but not between smoking and fibrosis or between RB and fibrosis. Fibrosis was significantly associated with silica (p = .004) and titanium (p = .0006) concentrations. The results support the authors' hypothesis.

Targeting epitopes in prostate-specific membrane antigen for antibody therapy of prostate cancer

Prostate-specific membrane antigen (PSMA) is a target for immunotherapy of prostate cancer. It has been shown that antibodies against PSMA inhibited the in vivo growth of LNCaP tumor. In the present study, monoclonal antibodies against four epitopes in PSMA were raised. MAb 24.4E6 (IgG1), specific for the epitope (residues 638-657) in PSMA, significantly reduced the growth rate of established LNCaP tumor in SCID mice. Mouse IgG was detected in the tumor of mice treated with 24.4E6, but not with an unrelated MAb. These results suggest that this epitope may be the main target in PSMA for antibody therapy of prostate cancer.

Role of embedded clustering in dilute magnetic semiconductors: Cr doped GaN

Results of extensive density-functional studies provide direct evidence that Cr atoms in Cr:GaN have a strong tendency to form embedded clusters, occupying Ga sites. Significantly, for larger than 2-Cr-atom clusters, states containing antiferromagnetic coupling with net spin in the range 0.06-1.47 muB/Cr are favored. We propose a picture where various configurations coexist and the statistical distribution and associated magnetism will depend sensitively on the growth details. Such a view may elucidate many puzzling observations related to the structural and magnetic properties of III-N and other dilute semiconductors.

Heterocyclic amines and genotype of N-acetyltransferases as risk factors for prostate cancer

A variety of carcinogenic heterocyclic amines are produced during the cooking of meat at high temperatures. These carcinogens are metabolized by N-acetyltransferases (NAT), which are polymorphic in the population. This study examined associations between prostate cancer (PCa) and the consumption of different kinds of meat, heterocyclic amine intake and NAT genotypes. PCa patients and controls were recruited in the Syracuse, NY area. Levels of meat and heterocyclic amine intakes were determined from validated surveys and NAT genotypes were determined by the sequences of PCR-amplified DNA from buccal swabs. A total of 152 cases and 161 controls were eligible for analysis. There was an association between PCa and history of PCa in the first-degree blood relatives (OR = 4.59, 95% CI 2.21-9.70), and family history of bladder cancer (P < 0.02). However, there was no association with the history of other cancers. There was no association between PCa and either 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) intake, or NAT1 and NAT2 genotypes. However, there was a trend of association with MeIQx and with rapid NAT2 and NAT1*10 in combination with PhIP. A new NAT1 allele with a frequency of one out of 544 chromosomes was found in the Caucasian subjects.

Half-metallicity and efficient spin injection in AlN/GaN:Cr (0001) heterostructure

First-principles investigations of the structural, electronic, and magnetic properties of Cr-doped AlN/GaN (0001) heterostructures reveal the possibility of efficient spin injection from a ferromagnetic GaN:Cr electrode through an AlN tunnel barrier. We demonstrate that Cr atoms segregate into the GaN region and that these interfaces retain their half-metallic behavior leading to a complete, i.e., 100%, spin polarization of the conduction electrons. This property makes the wide band-gap nitrides doped with Cr to be excellent candidates for high-efficiency magnetoelectronic devices.

Laser hair removal with alexandrite versus diode laser using four treatment sessions: 1-year results

BACKGROUND

Laser hair removal is the treatment of choice for hypertrichosis. The two most commonly used hair removal lasers are compared.

OBJECTIVE

To present the results of a comparative study examining the role of wavelength, fluence, spot size, pulse width, and cooling systems on long-term results after a series of four laser hair removal treatments using the 755 nm alexandrite and 800-810 nm diode lasers.

METHODS

The axillae of 15 untanned, type I-V patients were treated side by side four times at 4- to 6-week intervals with a 755 nm, 3-msec pulse width, cryogen spray-equipped alexandrite laser and an 800 nm, variable pulse width, cooled sapphire window-equipped diode laser. Each patient was pretested and treated with the maximum fluence tolerated at the largest spot size available for each laser (12 mm round/113 mm2 for the alexandrite and 9 mm for the diode).

RESULTS

Evaluations were done at 3, 6, 9, and 12 months after the last treatment. Twelve-month results with the alexandrite and diode lasers achieved 85% versus 84% hair reduction. The fact that tan avoidance was strictly followed permitted the use of relatively high fluences (25-30+ J/cm(2)) even in type IV patients. For most patients, four treatment sessions using high fluences (30-40 J/cm(2)) with relatively large spot sizes (12 mm round for the 755 nm alexandrite and 9 mm for the 800 nm diode) resulted in 12-month hair reductions in the 90% range.

CONCLUSION

Both the alexandrite and diode lasers in this 12-month study produced excellent long-term hair reductions.

Laser hair removal: long-term results with a 755 nm alexandrite laser

BACKGROUND

Hypertrichosis is a common problem for which laser hair removal is becoming the treatment of choice. Optimal wavelength, pulse duration, spot size, fluence, and skin cooling parameters for various skin types have not yet been firmly established.

OBJECTIVE

To evaluate the long-term efficacy and safety of a 3-msec 755 nm alexandrite laser equipped with a cryogen cooling device for patients with Fitzpatrick skin types I-V.

METHODS

Eighty-nine untanned patients with skin types I-V underwent a total of 492 treatments of laser hair removal over a 15-month period. Each patient in the study underwent a minimum of three treatment sessions spaced 4-6 weeks apart (mean treatments 5.6). Retrospective chart review and patient interviews were used to establish hair reduction results. Treatment sites included the axillae, bikini, extremities, face, and trunk. A 3-msec pulse width, 755 nm alexandrite laser equipped with a cryogen spray cooling device was used in this study. Spot sizes of 10-15 mm were used. A spot size of 10 mm was used for fluences greater than 40 J/cm(2), a spot size of 12 mm was used for fluences of 35-40 J/cm(2), and spot sizes of 12 and 15 mm were used for fluences less than 30 J/cm(2). Fluences ranging from 20 to 50 J/cm(2) (mean fluence 36 J/cm(2)) were used.

RESULTS

The patients had a mean 74% hair reduction. Skin type I patients had an average of 78.5% hair reduction using a mean fluence of 40 J/cm(2) (35-50 J/cm(2)) and a 10-12 mm spot size (12 mm in more than 95% of treatments). Skin type II patients had a mean 74.3% hair reduction using a mean fluence of 38 J/cm(2) (30-40 J/cm2) and a 12-15 mm spot size. Skin type III patients had a mean 73.4% hair reduction using a mean fluence of 37 J/cm(2) (25-40 J/cm(2)) and a 12-15 mm spot size. Skin type IV patients had a mean 71.0% hair reduction using a mean fluence of 31 J/cm2 (25-35 J/cm(2)) and a 12-15 mm spot size. A patient with skin type V had a 60% hair reduction using a mean fluence of 23 J/cm(2) (20-25 J/cm(2)) and a 12-15 mm spot size. The efficiency of hair removal directly correlates significantly with the fluence used. Rare side effects included transient postinflammatory hyperpigmentation (n = 9; 10%), burn with blisters (n = 1; 1%), and postinflammatory hypopigmentation (n = 2; 2%). All complications resolved without permanent scarring.

CONCLUSION

The 3-msec cryogen cooling-equipped alexandrite laser can safely and effectively achieve long-term hair removal in patients with skin types I-V. The best results are achieved in untanned patients with skin types I-IV.