120 research outputs found
Development of a Capacitive Mems RF Power Sensor Without Dissipative Losses: Towards a New Philosophy of RF Power Sensing
The development of a novel radio frequency (RF) power sensor is presented based on capacitive micro electromechanical system (MEMS) technology, in which the signal is barely disturbed during the power measurement. Results of the first prototypes and improvements for the second generation of RF power sensors are given\ud
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Radio frequency power sensor based on MEMS technology
We present the first measurement results of a power sensor for radio frequency (rf) signals (50 kHz - 40 GHz) with almost no dissipation during the measurement. This sensor is, therefore, a 'through' power sensor, that means that the rf signal is available during the measurement of its power. The power detection has been realized by measuring capacitively the movement of a grounded aluminum membrane, which is suspended above the transmission line carrying the rf signal. The power sensor is thus a capacitive MEMS technology based sensor. The fabrication is done by aluminum surface micromachining on an AF45 glass wafer. We measured the capacitance as a function of the applied rf power and found a linear relationship as predicted from theory
The EU's dependence on soya bean import for the animal feed industry and potential for EU produced alternatives
The European Innovation Partnership Agri has set up a consultation process involving 20 experts from 11 EU countries to discuss the potential of a substantial increase in protein crop production in the EU. The dependency of Europe on soya bean meal imports and the associated drivers are described and underline the need for change. The EIP Agri process resulted in the assessment of the present-day yield gap of protein crops using an approach based on the market values of the protein, starch and plant oil components. Oil-based protein crops seemed to be overall better positioned than starch based protein crops because the price of oil levels is higher than that of starch. Alfalfa was identified as being interesting for regions where drying cost are low. The process also resulted in the identification of opportunities and constraints to be encountered by the innovation process, combining the knowledge and physical infrastructure, market structure, co-operation and interaction and the influence of culturally determined values and beliefs. Therefore, the recommendation is to develop a comprehensive approach to meet the challenge of substantially increasing the EU’s protein crop production.Peer reviewe
Renal clearance of the thyrotropin-releasing hormone-like peptide pyroglutamyl-glutamyl-prolineamide in humans
TRH-like peptides have been identified that differ from TRH
(pGlu-His-ProNH2) in the middle amino acid. We have estimated TRH-like
immunoreactivity (TRH-LI) in human serum and urine by RIA with
TRH-specific antiserum 8880 or with antiserum 4319, which binds most
peptides with the structure pGlu-X-ProNH2. TRH was undetectable in serum
(< 25 pg/mL), but TRH-LI was detected with antiserum 4319 in serum of 27
normal subjects, 21 control patients, and 12 patients with carcinoid
tumors (range 17-45, 5-79, and 18-16,600 pg/mL, respectively). Because
serum was kept for at least 2 h at room temperature, which causes
degradation of TRH, pGlu-Phe-ProNH2, and pGlu-Tyr-ProNH2, serum TRH-LI is
not caused by these peptides. On high-performance liquid chromatography,
serum TRH-LI coeluted with pGlu-Glu-ProNH2 (< EEP-NH2), a peptide produced
in, among others, the prostate. Urine of normals and control patients also
contained TRH-LI (range 1.14-4.97 and 0.24-5.51 ng/mL, respectively), with
similar levels in males and females. TRH represented only 2% of urinary
TRH-LI, and anion-exchange chromatography and high-performance liquid
chromatography revealed that most TRH-LI in urine was < EEP-NH2. In
patients with carcinoid tumors, increased urinary TRH-LI levels were noted
(range 1.35-962.4 ng/mL). Urinary TRH-LI correlated positively with
urinary creatinine, and the urinary clearance rate of TRH-LI was similar
to the glomerular filtration rate. In addition, serum TRH-LI was increased
in 17 hemodialysis patients (43-373 pg/mL). This suggests that serum <
EEP-NH2 is cleared by glomerular filtration wit
Renal clearance of the thyrotropin-releasing hormone-like peptide pyroglutamyl-glutamyl-prolineamide in humans
TRH-like peptides have been identified that differ from TRH
(pGlu-His-ProNH2) in the middle amino acid. We have estimated TRH-like
immunoreactivity (TRH-LI) in human serum and urine by RIA with
TRH-specific antiserum 8880 or with antiserum 4319, which binds most
peptides with the structure pGlu-X-ProNH2. TRH was undetectable in serum
(< 25 pg/mL), but TRH-LI was detected with antiserum 4319 in serum of 27
normal subjects, 21 control patients, and 12 patients with carcinoid
tumors (range 17-45, 5-79, and 18-16,600 pg/mL, respectively). Because
serum was kept for at least 2 h at room temperature, which causes
degradation of TRH, pGlu-Phe-ProNH2, and pGlu-Tyr-ProNH2, serum TRH-LI is
not caused by these peptides. On high-performance liquid chromatography,
serum TRH-LI coeluted with pGlu-Glu-ProNH2 (< EEP-NH2), a peptide produced
in, among others, the prostate. Urine of normals and control patients also
contained TRH-LI (range 1.14-4.97 and 0.24-5.51 ng/mL, respectively), with
similar levels in males and females. TRH represented only 2% of urinary
TRH-LI, and anion-exchange chromatography and high-performance liquid
chromatography revealed that most TRH-LI in urine was < EEP-NH2. In
patients with carcinoid tumors, increased urinary TRH-LI levels were noted
(range 1.35-962.4 ng/mL). Urinary TRH-LI correlated positively with
urinary creatinine, and the urinary clearance rate of TRH-LI was similar
to the glomerular filtration rate. In addition, serum TRH-LI was increased
in 17 hemodialysis patients (43-373 pg/mL). This suggests that serum <
EEP-NH2 is cleared by glomerular filtration with little tubular
resorption. The possible role of the prostate as a source of urinary
TRH-LI was evaluated in 11 men with prostate cancer, showing a 25%
decrease in urinary TRH-LI excretion after prostatectomy (0.19 +/- 0.02
vs. 0.15 +/- 0.01 ng/mumol creatinine, mean +/- SEM). However, TRH-LI was
similar in spontaneously voided urine and in urine obtained through a
nephrostomy cannula from 16 patients with unilateral urinary tract
obstruction (0.15 +/- 0.01 vs. 0.14 +/- 0.01 ng/mumol creatinine). These
data indicate that: 1) TRH-LI in human serum represents largely < EEP-NH2,
which is cleared by renal excretion; 2) part of urinary < EEP-NH2 is
derived from prostatic secretion into the blood and not directly into
urine; and 3) urinary < EEP-NH2 can be used as marker for carcinoid
tumors
Dynamic phase-locking states and personality in sub-acute mild traumatic brain injury:An exploratory study
Research has shown that maladaptive personality characteristics, such as Neuroticism, are associated with poor outcome after mild traumatic brain injury (mTBI). The current exploratory study investigated the neural underpinnings of this process using dynamic functional network connectivity (dFNC) analyses of resting-state (rs) fMRI, and diffusion MRI (dMRI). Twenty-seven mTBI patients and 21 healthy controls (HC) were included. After measuring the Big Five personality dimensions, principal component analysis (PCA) was used to obtain a superordinate factor representing emotional instability, consisting of high Neuroticism, moderate Openness, and low Extraversion, Agreeableness, and Conscientiousness. Persistent symptoms were measured using the head injury symptom checklist at six months post-injury; symptom severity (i.e., sum of all items) was used for further analyses. For patients, brain MRI was performed in the sub-acute phase (~1 month) post-injury. Following parcellation of rs-fMRI using independent component analysis, leading eigenvector dynamic analysis (LEiDA) was performed to compute dynamic phase-locking brain states. Main patterns of brain diffusion were computed using tract-based spatial statistics followed by PCA. No differences in phase-locking state measures were found between patients and HC. Regarding dMRI, a trend significant decrease in fractional anisotropy was found in patients relative to HC, particularly in the fornix, genu of the corpus callosum, anterior and posterior corona radiata. Visiting one specific phase-locking state was associated with lower symptom severity after mTBI. This state was characterized by two clearly delineated communities (each community consisting of areas with synchronized phases): one representing an executive/saliency system, with a strong contribution of the insulae and basal ganglia; the other representing the canonical default mode network. In patients who scored high on emotional instability, this relationship was even more pronounced. Dynamic phase-locking states were not related to findings on dMRI. Altogether, our results provide preliminary evidence for the coupling between personality and dFNC in the development of long-term symptoms after mTBI.</p
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