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A sustainable synthetic route for biobased 6-hydroxyhexanoic acid, adipic acid and ϵ-caprolactone by integrating bio- And chemical catalysis

A green route for the production of 6-carbon polymer building blocks 6-hydroxyhexanoic acid, adipic acid and ϵ-caprolactone from 1,6-hexanediol, a hydrogenation product of biobased 5-hydroxymethylfurfural is reported. Gluconobacter oxydans oxidized 1,6-hexanediol completely to adipic acid, and selectively at pH 6-7 to 6-hydroxyhexanoic acid, which was converted to ϵ-caprolactone by catalytic cycli

6G Wireless Systems: Vision, Requirements, Challenges, Insights, and Opportunities

Mobile communications have been undergoing a generational change every ten years or so. However, the time difference between the so-called "G's" is also decreasing. While fifth-generation (5G) systems are becoming a commercial reality, there is already significant interest in systems beyond 5G, which we refer to as the sixth-generation (6G) of wireless systems. In contrast to the already published

A scintillation camera technique for measurements of the reticuloendothelial function -Comparison of different methods for measuring RES function

A highly standardized 99mTc-sulphur colloid was used to evaluate reticuloendothelial system (RES)-function in the normal rat and after RE blockade by gelatin (Haemaccel). Activity distribution in the animals was measured with a scintillation camera technique. Total uptake of activity in the liver was estimated. From the time-activity curves over the liver, the phagocytic index (kphag) was evaluate

Factors affecting the trapping performance of xenon holdup-filters in nuclear medicine applications

Activated charcoal traps are used in nuclear medicine departments to capture exhaled radioactive xenon gas. In the present study, the trapping performance of charcoal was investigated for different physical qualities in experimental and clinical situations. Various factors affecting the trapping capacity are identified, such as the charcoal mass, moisture and carbon�dioxide concentrations in the

Experimental set-up for studies of microwave-induced hyperthermia in rats

A low-cost microprocessor-based temperature controller for hyperthermia experiments on rats is described. The system directs a microwave generator, used for heating, by feedback power regulating signals in accordance with the temperature in the animal. The microwave power is pulsed for short on-and-off periods and the temperature recordings are carried out during the off periods. More than 300 hyp

Dosimetry in lymphoscintigraphy of Tc-99m antimony sulfide colloid

A quantitative kinetic technique using a scintillation camera has been developed for investigating lymph drainage and the uptake in the lymph nodes of 99mTcSb2S3 colloid injected subcutaneously. Twenty-two patients with primary malignant melanoma were examined. Lymph-node dissection was performed and 185 lymph nodes were individually measured for radioactivity. The kinetics of colloid uptake in in

A new instrument for survey monitoring of airborne xenon-133

Methods are reviewed for measuring xenon-133 contamination of the air in medical clinics. The principles of a new, simple, and low cost monitor are outlined. Results from experimental tests in laboratories and medical clinics were encouraging, indicating that the monitor is a valuable tool for survey measurements of 133Xe contamination in nuclear medicine departments.

Quality control of 99mTc-radiopharmaceuticals - Evaluation of GCS minicolumns in routine clinical work with scintillation cameras

Gel chromatography column scanning (GCS) is a rapid and reliable method for the quality control of 99mTc-radiopharmaceuticals. With this method the labelled compound and various impurities such as free pertechnetate, hydrolyzed reduced technetium or other 99mTc-complexes are obtained in one testing procedure. Using minicolumns results can be obtained with a simple testing procedure within a few mi

Blood flow in experimental liver tumors : Effect of vasoactive drugs

The effects of infused glucagon, histamine and vasopressin on blood flow in anesthetized rats with intrahepatic tumors were studied using microspheres labelled with 99Tcm or 51Cr isotopes. Considerable circulatory effects were noted both in central hemodynamic parameters as well as in organ and tissue blood flows. Glucagon infusion increased blood flow in the spleen and small intestine while hepat

Influence of vasoactive drugs on blood flow in subcutaneous tumors – an experimental study in rats

Subcutaneously implanted tumors in Wistar and Lister rats were used as a model for the study of metastatic tumor blood flow and how it is affected by vasoactive drugs. Blood flow measurements were obtained using the labelled microsphere method and the reference organ technique. Microspheres (15‐μm) labelled with either 99Tcm or 51 Cr isotopes were injected intracardially and a reference sample was

Quantitative lymphoscintigraphy. I. Basic concepts for optimal uptake of radiocolloids in the parasternal lymph nodes of rabbits

The activity-size distribution of radiocolloids has been studied using gel-chromatography scanning (GCS) of columns filled with Sepharose 4B gel. Rabbits were injected subcutaneously with the colloid of interest, laid supine beneath a gamma camera, and imaged every 15 sec for 2 to 4 hr. From the stored data, the uptakes in the parasternal lymph nodes were analyzed in terms of a two-compartment mod

Measurements of cardiac output and organ blood flow in rats using 99Tcm labelled microspheres

The cardiac output and regional blood flow have been simultaneously determined in the anesthetized rat by using the reference organ method. 99Tcm labelled dextran 15 μm microspheres were injected in the left ventricle while simultaneously an arterial reference sample was drawn at constant known rate. The values calculated regarding cardiac output agree well with previously recorded series. Regiona

Unequal Extractions : Reconceptualizing the Chinese Miner in Ghana

Over the past decade, Chinese migration to Africa has increased rapidly alongside the expansion of Chinese economic engagement with the continent. The entrance of new forms of Chinese industry, aid, commerce and resource exploration has been transformative, prompting debates over whether China in Africa is better described as neo-colonialism or a new form of beneficial developmentalism. One of the

Några reflexioner kringbegreppet ”arbetararistokrati”

I en efterskrift till boken ”Arbetararistokratin. En begreppsarkeologi” resonerar jag kring varför begreppet ”arbetararistokrati” en gång tycktes värt att analysera så pass ingående som jag gjorde. Jag anför däri 1960- och 1970-talens livaktiga samhällsvetenskapliga forskning och diskussion om arbetarklassens förborgerligande och avradikalisering. Det övergripande problem som framträder är förhåll

Arbetararistokratin : En begreppsarkeologi

I mitten av 1970-talet skrev jag tre artiklar om begreppet ”arbetararistokrati” vilka publicerades i tidskriften Arkiv för studier i arbetarrörelsens historia under rubrikerna ”Teorier om reformism och arbetararistokrati hos Engels och Lenin” nr 6 (1974), ”Arbetararistokrati och reformism. Del I: Den kommunistiska traditionen efter Lenin” i nr 11–12 (1977) samt ”Arbetararistokrati och reformism. D

An affordances apparatus for enterprise social media

The current paper addresses one of the core yet complex issues in the study of technology in organizations: the relationship between the social and the material. Many scholars in the field of Information Systems have used the notion of affordance as a lens to investigate and theorize this relationship. However, knowledge contributions in this area are often abstract and impractical, or at least co