Design of millimetre-wave antennas on low temperature co-fired ceramic substrates

Tässä työssä tutkitaan millimetriaaltoalueella toimivien, LTCC- monikerroskeraamitekniikalla valmistettujen, antennien toteutusmahdollisuuksia. Erityisesti keskitytään 60 GHz taajuudella toimivien mikroliuska-antennien suunnitteluun, mallintamiseen, valmistukseen ja testaamiseen. LTCC-tekniikka on nykyaikainen pakkaustekniikka, jolla voidaan valmistaa laadukkaita monikerroksisia komponentteja ja moduuleja jopa millimetriaaltotaajuuksille asti. LTCC-tekniikan hyötyjä ovat suuri pakkaustiheys, matalat eriste- ja johdinhäviöt, luotettavuus ja vakaus. LTCC-tekniikan suurimpia haasteita on valmistusepätarkkuus, joka muodostuu ratkaisevaksi tekijäksi 60 GHz taajuudella toimivien antennien suorituskyvylle. Kirjallisuuskatsauksessa esitellään antenniteorian perusteet ja yleisiä antennien ominaissuureita. Myös antenniryhmän käsitteet esitellään. Tämän jälkeen tarkastellaan mikroliuska-antennien ominaisuuksia, jonka jälkeen perehdytään LTCC-tekniikkaan. Työssä suunnitellaan usean tyyppisiä mikroliuska-antenneja ja antennit mallinnetaan käyttäen kaupallisia ohjelmia. Antenneja simuloidaan myös käyttäen itse kirjoitettua ohjelmakoodia. Antennien toimivuus varmistetaan käytännössä suorittamalla sirontaparametri- ja säteilykuviomittaukset. Mittaus- ja simulointitulokset ovat melko yhteneviä. Pienet poikkeavuudet tuloksissa johtuvat antennien toteutuneiden ja suunniteltujen mittojen eroavaisuuksista. Kuitenkin, paluuvaimennuksen arvoksi saadaan helposti -10 dB tai parempi. Impedanssikaistanleveys vaihtelee välillä 3...6 % ja antennien maksimivahvistus välillä 3...4 dB. Tulosten perusteella voidaan todeta, että perinteisen LTCC-tekniikan avulla voidaan toteuttaa toimivia antenneja jopa 60 GHz taajuudelle.In this work, implementation possibilities of millimetre-wave antennas fabricated with low temperature co-fired ceramic (LTCC) technology are investigated. Especially, microstrip antennas operating at 60 GHz frequency band are designed, modeled, manufactured and tested. LTCC is a modern packaging technology which enables manufacturing of multilayer components and modules with high performance up to millimetre-wave region. Benefits of the LTCC technology are high packaging density, low dielectric and conductor losses, reliability and stability. The challenges of the LTCC technology are related to the manufacturing tolerances which become critical for operation of the antennas at 60 GHz frequency band. In the literature review, the basics of antenna theory are presented and common antenna parameters are introduced. Issues related to antenna arrays are also introduced. Then, basic characteristics of microstrip antennas are presented, followed by the introduction of the LTCC technology. Several types of microstrip antennas are designed and modeled with numerical simulation software. Two types of antennas are also modeled with simulation code implemented by the author. The functionality of fabricated antennas is validated by conducting scattering parameter and radiation pattern measurements. Measurement results agree quite well with the simulated ones. Small deviations between simulated and measured results are caused by the differences in designed and realised dimensions of the antennas. Return loss of -10 dB or better is easily achieved. Impedance bandwidth of the antennas is in the order of 3...6 %. Maximum absolute gains vary between 3...4 dB. It is clearly seen from the results that functional antennas can be fabricated with standard LTCC process and materials even for the 60 GHz frequency band

Treatment of shoulder sequelae in brachial plexus birth injury

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Graphene-Flakes Printed Wideband Elliptical Dipole Antenna for Low Cost Wireless Communications Applications

This letter presents the design, manufacturing and operational performance of a graphene-flakes based screenprinted wideband elliptical dipole antenna operating from 2 GHz up to 5 GHz for low cost wireless communications applications. To investigate radio frequency (RF) conductivity of the printed graphene, a coplanar waveguide (CPW) test structure was designed, fabricated and tested in the frequency range from 1 GHz to 20 GHz. Antenna and CPW were screen-printed on Kapton substrates using a graphene paste formulated with a graphene to binder ratio of 1:2. A combination of thermal treatment and subsequent compression rolling is utilized to further decrease the sheet resistance for printed graphene structures, ultimately reaching 4 Ohm/sq. at 10 {\mu}m thicknesses. For the graphene-flakes printed antenna an antenna efficiency of 60% is obtained. The measured maximum antenna gain is 2.3 dBi at 4.8 GHz. Thus the graphene-flakes printed antenna adds a total loss of only 3.1 dB to an RF link when compared to the same structure screen-printed for reference with a commercial silver ink. This shows that the electrical performance of screen-printed graphene flakes, which also does not degrade after repeated bending, is suitable for realizing low-cost wearable RF wireless communication devices.Comment: Accepted, in press (online preview available

Decreased Aerobic Capacity in ANO5-Muscular Dystrophy

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PRISM : recovering cell-type-specific expression profiles from individual composite RNA-seq samples

Motivation: A major challenge in analyzing cancer patient transcriptomes is that the tumors are inherently heterogeneous and evolving. We analyzed 214 bulk RNA samples of a longitudinal, prospective ovarian cancer cohort and found that the sample composition changes systematically due to chemotherapy and between the anatomical sites, preventing direct comparison of treatment-naive and treated samples. Results: To overcome this, we developed PRISM, a latent statistical framework to simultaneously extract the sample composition and cell-type-specific whole-transcriptome profiles adapted to each individual sample. Our results indicate that the PRISM-derived composition-free transcriptomic profiles and signatures derived from them predict the patient response better than the composite raw bulk data. We validated our findings in independent ovarian cancer and melanoma cohorts, and verified that PRISM accurately estimates the composition and cell-type-specific expression through whole-genome sequencing and RNA in situ hybridization experiments.Peer reviewe

Longitudinal single-cell RNA-seq analysis reveals stress-promoted chemoresistance in metastatic ovarian cancer

Chemotherapy resistance is a critical contributor to cancer mortality and thus an urgent unmet challenge in oncology. To characterize chemotherapy resistance processes in high-grade serous ovarian cancer, we prospectively collected tissue samples before and after chemotherapy and analyzed their transcriptomic profiles at a single-cell resolution. After removing patient-specific signals by a novel analysis approach, PRIMUS, we found a consistent increase in stress-associated cell state during chemotherapy, which was validated by RNA in situ hybridization and bulk RNA sequencing. The stress-associated state exists before chemotherapy, is subclonally enriched during the treatment, and associates with poor progression-free survival. Co-occurrence with an inflammatory cancer-associated fibroblast subtype in tumors implies that chemotherapy is associated with stress response in both cancer cells and stroma, driving a paracrine feed-forward loop. In summary, we have found a resistant state that integrates stromal signaling and subclonal evolution and offers targets to overcome chemotherapy resistance.Peer reviewe

Detection of Prostate Cancer Using Biparametric Prostate MRI, Radiomics, and Kallikreins : A Retrospective Multicenter Study of Men With a Clinical Suspicion of Prostate Cancer

Background Accurate detection of clinically significant prostate cancer (csPCa), Gleason Grade Group >= 2, remains a challenge. Prostate MRI radiomics and blood kallikreins have been proposed as tools to improve the performance of biparametric MRI (bpMRI). Purpose To develop and validate radiomics and kallikrein models for the detection of csPCa. Study Type Retrospective. Population A total of 543 men with a clinical suspicion of csPCa, 411 (76%, 411/543) had kallikreins available and 360 (88%, 360/411) did not take 5-alpha-reductase inhibitors. Two data splits into training, validation (split 1: single center, n = 72; split 2: random 50% of pooled datasets from all four centers), and testing (split 1: 4 centers, n = 288; split 2: remaining 50%) were evaluated. Field strength/Sequence A 3 T/1.5 T, TSE T2-weighted imaging, 3x SE DWI. Assessment In total, 20,363 radiomic features calculated from manually delineated whole gland (WG) and bpMRI suspicion lesion masks were evaluated in addition to clinical parameters, prostate-specific antigen, four kallikreins, MRI-based qualitative (PI-RADSv2.1/IMPROD bpMRI Likert) scores. Statistical Tests For the detection of csPCa, area under receiver operating curve (AUC) was calculated using the DeLong's method. A multivariate analysis was conducted to determine the predictive power of combining variables. The values of P-value < 0.05 were considered significant. Results The highest prediction performance was achieved by IMPROD bpMRI Likert and PI-RADSv2.1 score with AUC = 0.85 and 0.85 in split 1, 0.85 and 0.83 in split 2, respectively. bpMRI WG and/or kallikreins demonstrated AUCs ranging from 0.62 to 0.73 in split 1 and from 0.68 to 0.76 in split 2. AUC of bpMRI lesion-derived radiomics model was not statistically different to IMPROD bpMRI Likert score (split 1: AUC = 0.83, P-value = 0.306; split 2: AUC = 0.83, P-value = 0.488). Data Conclusion The use of radiomics and kallikreins failed to outperform PI-RADSv2.1/IMPROD bpMRI Likert and their combination did not lead to further performance gains. Level of Evidence 1 Technical Efficacy Stage 2Peer reviewe

PRISM: Recovering cell type specific expression profiles from individual composite RNA-seq samples

Motivation: A major challenge in analyzing cancer patient transcriptomes is that the tumors are inherently heterogeneous and evolving. We analyzed 214 bulk RNA samples of a longitudinal, prospective ovarian cancer cohort and found that the sample composition changes systematically due to chemotherapy and between the anatomical sites, preventing direct comparison of treatment-naive and treated samples.Results: To overcome this, we developed PRISM, a latent statistical framework to simultaneously extract the sample composition and cell type specific whole-transcriptome profiles adapted to each individual sample. Our results indicate that the PRISM-derived composition-free transcriptomic profiles and signatures derived from them predict the patient response better than the composite raw bulk data. We validated our findings in independent ovarian cancer and melanoma cohorts, and verified that PRISM accurately estimates the composition and cell type specific expression through whole-genome sequencing and RNA in situ hybridization experiments.</p

Longitudinal single-cell RNA-seq analysis reveals stress-promoted chemoresistance in metastatic ovarian cancer

Chemotherapy resistance is a critical contributor to cancer mortality and thus an urgent unmet challenge in oncology. To characterize chemotherapy resistance processes in high-grade serous ovarian cancer, we prospectively collected tissue samples before and after chemotherapy and analyzed their transcriptomic profiles at a single-cell resolution. After removing patient-specific signals by a novel analysis approach, PRIMUS, we found a consistent increase in stress-associated cell state during chemotherapy, which was validated by RNA in situ hybridization and bulk RNA sequencing. The stress-associated state exists before chemotherapy, is subclonally enriched during the treatment, and associates with poor progression-free survival. Co-occurrence with an inflammatory cancer-associated fibroblast subtype in tumors implies that chemotherapy is associated with stress response in both cancer cells and stroma, driving a paracrine feed-forward loop. In summary, we have found a resistant state that integrates stromal signaling and subclonal evolution and offers targets to overcome chemotherapy resistance

Validation of IMPROD biparametric MRI in men with clinically suspected prostate cancer: A prospective multi-institutional trial

Background: Magnetic resonance imaging (MRI) combined with targeted biopsy (TB) is increasingly used in men with clinically suspected prostate cancer (PCa), but the long acquisition times, high costs, and inter-center/reader variability of routine multiparametric prostate MRI limit its wider adoption.Methods and findings: The aim was to validate a previously developed unique MRI acquisition and reporting protocol, IMPROD biparametric MRI (bpMRI) (NCT01864135), in men with a clinical suspicion of PCa in a multi-institutional trial (NCT02241122). IMPROD bpMRI has average acquisition time of 15 minutes (no endorectal coil, no intravenous contrast use) and consists of T2-weighted imaging and 3 separate diffusion-weighed imaging acquisitions. Between February 1, 2015, and March 31, 2017, 364 men with a clinical suspicion of PCa were enrolled at 4 institutions in Finland. Men with an equivocal to high suspicion (IMPROD bpMRI Likert score 3-5) of PCa had 2 TBs of up to 2 lesions followed by a systematic biopsy (SB). Men with a low to very low suspicion (IMPROD bpMRI Likert score 1-2) had only SB. All data and protocols are freely available. The primary outcome of the trial was diagnostic accuracy-including overall accuracy, sensitivity, specificity, negative predictive value (NPV), and positive predictive value-of IMPROD bpMRI for clinically significant PCa (SPCa), which was defined as a Gleason score >= 3 + 4 (Gleason grade group 2 or higher). In total, 338 (338/364, 93%) prospectively enrolled men completed the trial. The accuracy and NPV of IMPROD bpMRI for SPCa were 70% (113/161) and 95% (71/75) (95% CI 87%-98%), respectively. Restricting the biopsy to men with equivocal to highly suspicious IMPROD bpMRI findings would have resulted in a 22% (75/338) reduction in the number of men undergoing biopsy while missing 4 (3%, 4/146) men with SPCa. The main limitation is uncertainty about the true PCa prevalence in the study cohort, since some of the men may have PCa despite having negative biopsy findings.Conclusions: IMPROD bpMRI demonstrated a high NPV for SPCa in men with a clinical suspicion of PCa in this prospective multi-institutional clinical trial.</p