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Photochemistry of diiodomethane in solution studied by femtosecond and nanosecond laser photolysis. Formation and dark reactions of the CH2I-I isomer photoproduct and its role in cyclopropanation of olefins

Femtosecond and nanosecond photolysis of CH2I2 in acetonitrile at an excitation wavelength of 266-nm yield the ground-state CH2I-I isomer product in similar to70% quantum yield. High isomer formation quantum yields (> 70%) were measured also in n-hexane, dichloromethane, methanol, and ethanol using nanosecond photolysis. The CH2I-I product is formed biphasically within similar to15 ps after excita

In vivo absorbed dose measurements in mammography using a new real-time luminescence technique

A dosimetry system based on radioluminescence (RL) and optically stimulated luminescence (OSL) from carbon doped aluminium oxide (Al2O3:C) crystals was developed for in vivo absorbed dose measurements in mammography. A small cylindrical crystal of Al2O3:C (diameter 0.48 mm and length 2 mm) was coupled to the end of a 1 mm diameter optical fibre cable. Owing to their small size and characteristic s

A Detailed Kinetic Model for Calculation of the Soot Particle Size Distribution Function

The soot particle size distribution was studied via numerical simulation under diesel like engine conditions using a detailed kinetic soot model. Two different mathematical methods of the soot model description have been used in this work. In the first part of the work, the method of moments is presented. In addition, a so called sectional method for the soot particle size distribution function in

Development of a solid-phase extraction method for the determination of polychlorinated biphenyls in water

Polychlorinated biphenyls (PCBs) in water were extracted with a rebuilt extraction unit using 47 mm C18 solid-phase extraction (SPE) disks. Three types of disks (SPEC, ENVI and Empore) were investigated for the extraction of seven PCBs from 1 l reagent water spiked at two concentration levels (20 and 1000 ng/l). The Empore disks produced the best analyte recoveries (91–107% with R.S.D. of 1–8%) at

Det manliga klimakteriet: om försöket att lansera ett medicinskt begrepp

Är du en surgubbe?” frågar kvällstidningen Aftonbladet i en artikelrubrik. I så fall kan du ha hamnat i det manliga klimakteriet. Allt oftare talas det idag om ett manligt klimakterium. Ämnet väcker allmänhetens uppmärksamhet. Därigenom vinner föreställningen om att män i medelåldern drabbas av besvär och förlorar sin ’manlighet’ i en nedbrytande klimakterieprocess utbredning i samhället. Tanken p

Monitoring of persistent organic pollutants (POPs): Examples from Lake Vattern, Sweden

Lake Vattern in southern Sweden is a large oligotrophic lake with high surface to catchment area ratio (ca. 0.4) and a water residence time of 60 years. The lake combines sensitivity to atmospheric POP-pollution with general susceptibility for effects of POPs and slow concentration decline. Time series, from the 1960s until 1996, of PCBs and DDT in fish and data on TCDD in sediment of L. Vattern a

Eclampsia in Scandinavia: incidence, substandard care, and potentially preventable cases

Background. Description of incidence, clinical signs, symptoms, and consequences of eclampsia in Scandinavia, and assessment of substandard care and potential preventability. Methods. A descriptive cohort study including all women giving birth in a 2-year period (mid-1998-mid-2000) in Scandinavia. Notifications of eclampsia cases were obtained from all obstetric units at 3-monthly intervals. All p

Biosensors for life quality - Design, development and applications

Biosensors, combining a selective biological recognition element and a sensitive transducer, are versatile analytical tools applied more and more in different fields, such as medicine, food quality and safety control, and environment pollution monitoring. They are expected to play an increasingly important role in the improvement of life quality. In this context, the present work covers recent app

Synthesis of naphthoxylosides on solid support

In order to investigate the selective antiproliferative effects shown by 2-(6-hydroxynaphthyl)-beta-D-xylopyranoside the 14 possible beta-D-xylopyranosidic compounds were synthesized on solid support. An aminomethylated polystyrene resin was converted into an acid chloride resin and then esterified using dihydroxynaphthalene. The free hydroxy group was then xylosylated Under BF3.OEt2 mediated cond

The risk and burden of vertebral fractures in Sweden

The aim of this study was to determine the risk and burden of vertebral fractures judged as those coming to clinical attention and as morphometric fractures. Incidence and utility loss were computed from data from Malmo, Sweden. Clinical fractures accounted for 23% of all vertebral deformities in women and for 42% in men. The average 10-year fracture probability for morphometric fractures increase

Snowmelt sensitivity to radiation in the urban environment

Despite having the same snowmelt processes, snowpacks in urban environments experience a range of conditions different from those of rural areas. Melt is intensified at some sites due to greater radiative energy. Shading, however, can reduce radiation and melt at other sites. Changes to the radiation balance and snowpack processes have been investigated. A physical snowpack model was developed and

Compact archaeal variant of heme A synthase

The N- and C-terminal halves of the heme A synthase polypeptide of Bacillus subtilis, and many other organisms, are homologous. This indicates that these enzyme proteins originate from a tandem duplication and fusion event of a gene encoding a protein half as large. The ape1694 gene of the hyperthermophilic archaeon Aeropyrum pernix encodes a protein that is similar to the hypothetical small primo

Development of biosensors based on hexacyanoferrates.

Ferric and copper hexacyanoferrates (PB and CuHCF, respectively) were electrodeposited on glassy carbon electrodes providing a suitable catalytic surface for the amperometric detection of hydrogen peroxide. Additionally glucose oxidase was immobilized on top of these electrodes to form glucose biosensors. The biosensors were made by casting glucose oxidase-Nafion layers onto the surface of the mod

Proliferative index obtained by DNA image cytometry. Does it add prognostic information in Auer IV breast cancer?

OBJECTIVE: To investigate whether the S + G2/M fraction (proliferative index) is a prognostic determinant in breast cancers classified as Auer IV. STUDY DESIGN: Prognostic evaluation of Auer IV DNA histograms with respect to the high versus low S + G2/M fraction, obtained by image cytometry on consecutive breast cancer imprint preparations. RESULTS: When studying recurrence-free survival (n = 136)

The restricted active space (RAS) state interaction approach with spin-orbit coupling

A method to compute spin-orbit coupling between electronic states is presented. An effective one-electron spin-orbit Hamiltonian is used, based on atomic mean field integrals, The basic electronic states are obtained using the restricted active space (RAS) SCF method. The Hamiltonian matrix is obtained by an extension of the restricted active space state interaction (RASSI) method. Several hundred