39 research outputs found
Unveiling the significance of eigenvectors in diffusing non-hermitian matrices by identifying the underlying Burgers dynamics
Following our recent letter, we study in detail an entry-wise diffusion of
non-hermitian complex matrices. We obtain an exact partial differential
equation (valid for any matrix size and arbitrary initial conditions) for
evolution of the averaged extended characteristic polynomial. The logarithm of
this polynomial has an interpretation of a potential which generates a Burgers
dynamics in quaternionic space. The dynamics of the ensemble in the large
is completely determined by the coevolution of the spectral density and a
certain eigenvector correlation function. This coevolution is best visible in
an electrostatic potential of a quaternionic argument built of two complex
variables, the first of which governs standard spectral properties while the
second unravels the hidden dynamics of eigenvector correlation function. We
obtain general large formulas for both spectral density and 1-point
eigenvector correlation function valid for any initial conditions. We exemplify
our studies by solving three examples, and we verify the analytic form of our
solutions with numerical simulations.Comment: 24 pages, 11 figure
Dynamical Isometry is Achieved in Residual Networks in a Universal Way for any Activation Function
We demonstrate that in residual neural networks (ResNets) dynamical isometry
is achievable irrespectively of the activation function used. We do that by
deriving, with the help of Free Probability and Random Matrix Theories, a
universal formula for the spectral density of the input-output Jacobian at
initialization, in the large network width and depth limit. The resulting
singular value spectrum depends on a single parameter, which we calculate for a
variety of popular activation functions, by analyzing the signal propagation in
the artificial neural network. We corroborate our results with numerical
simulations of both random matrices and ResNets applied to the CIFAR-10
classification problem. Moreover, we study the consequence of this universal
behavior for the initial and late phases of the learning processes. We conclude
by drawing attention to the simple fact, that initialization acts as a
confounding factor between the choice of activation function and the rate of
learning. We propose that in ResNets this can be resolved based on our results,
by ensuring the same level of dynamical isometry at initialization
Dysonian dynamics of the Ginibre ensemble
We study the time evolution of Ginibre matrices whose elements undergo
Brownian motion. The non-Hermitian character of the Ginibre ensemble binds the
dynamics of eigenvalues to the evolution of eigenvectors in a non-trivial way,
leading to a system of coupled nonlinear equations resembling those for
turbulent systems. We formulate a mathematical framework allowing simultaneous
description of the flow of eigenvalues and eigenvectors, and we unravel a
hidden dynamics as a function of new complex variable, which in the standard
description is treated as a regulator only. We solve the evolution equations
for large matrices and demonstrate that the non-analytic behavior of the
Green's functions is associated with a shock wave stemming from a Burgers-like
equation describing correlations of eigenvectors. We conjecture that the hidden
dynamics, that we observe for the Ginibre ensemble, is a general feature of
non-Hermitian random matrix models and is relevant to related physical
applications.Comment: 5 pages, 2 figure
Rola HE4 w r贸偶nicowaniu z艂o艣liwych i niez艂o艣liwych patologii endometrium
Objectives: The incidence of endometrial cancer is constantly growing. More aggressive types of endometrial cancer as well as the incidence in younger women is being observed. More than 80% of cases is diagnosed in early stages due to early symptoms like abnormal bleeding. The remaining 20% of asymptomatic cases of endometrial cancer as well as the cases of false negative histopathological diagnoses are mostly the incidences of serous endometrial cancer and are a true diagnostic and therapeutic challenge. This was the reason of our study in which we proposed investigation of HE4 levels as a complementary diagnostic method in management and diagnosing of EC.
Material and methods: Serum HE4 level was measured in 92 patients with abnormal vaginal bleeding. Based on histhology after curretage the study group was divided into the benign and malignant endometrial pathology groups. Statistical analysis was performed using Mann-Whitney test
Results: The difference of serum HE4 level between benign endometrial pathology and cancer was significant (p = 0.000) and the cut-off for identification of patients with endometrial cancer was 58.08 pmol/l. There was a significant difference between G2 and G3 endometrial cancer, and G1 and G3. (p = 0,4 and p = 0,008 respectively) Patients who needed lymphadenectomy had significantly higher HE4 level than those who had no indications for this procedure (p = 0,001).
Conclusions: HE4 is a useful biomarker in diagnosing endometrial cancer. HE4 is associated with high grade endometrial cancer. It can also serve as an useful preoperative counseling tool to identify patients, who may require pelvic and paraaortic lymphadenectomy.Obecnie obserwuje si臋 wzrost zapadalno艣ci na raka endometrium, w szczeg贸lno艣ci bardziej agresywnych typ贸w tej choroby oraz jej wyst臋powanie u coraz m艂odszych pacjentek. Wprawdzie wi臋cej ni偶 80% przypadk贸w jest diagnozowanych we wczesnych stadiach zaawansowania, dzi臋ki wczesnych objawom, takim jak nieprawid艂owe krwawienia. Jednak pacjentki bezobjawowe, jak r贸wnie偶 przypadki fa艂szywie negatywnych wynik贸w histopatologicznych s膮 wyzwaniem diagnostycznym i terapeutycznym. W niniejszej pracy dokonano analizy warto艣ci bia艂ka HE4 jako metody uzupe艂niaj膮cej diagnostyk臋 raka endometrium.
Materia艂 i metody: St臋偶enie markera w surowicy krwi zosta艂o oznaczone u 92 pacjentek z nieprawid艂owymi krwawieniami. Opieraj膮c si臋 na wyniku badania histopatologicznego zosta艂y podzielone na grup臋 z niez艂o艣liwymi i z艂o艣liwymi zmianami endometrium. Analiza statystyczna zosta艂a wykonana za pomoc膮 testu Mann-Withney.
Wyniki: R贸偶nica st臋偶enia HE4 mi臋dzy zmianami niez艂o艣liwymi endometrium a rakiem by艂a istotna statystycznie (p = 0,000) i warto艣膰 odci臋cia wynios艂a 58,08 pmol/l. R贸偶nica st臋偶enia HE4 w stopniu z艂o艣liwo艣ci raka endometrium G2 i G3 by艂a istotna statystycznie jak r贸wnie偶 mi臋dzy G1 a G3 (p= 0,4 i p = 0,008 odpowiednio). Pacjentki, kt贸re wymaga艂y limfadenektomii mia艂y istotnie wy偶sze st臋偶enia HE4 od tych, kt贸re nie wymaga艂y takiego post臋powania (p = 0,001).
Wnioski: HE4 jest u偶ytecznym biomarkerem raka endometrium. Jest zwi膮zany z niskim stopniem zr贸偶nicowania nowotworu. HE4 mo偶e by膰 u偶yteczne w identyfikacji pacjentek wymagaj膮cych oko艂oaortalnej i miednicznej limfadenektomii
Psychoeducation and psychological prevention for family members of schizophrenic patients : the project report
Wysoka ekspresja WFDC2 w raku jajnika oraz prawid艂owym jajowodzie nie koreluje z poziomem HE4 w surowicy krwi
Objectives: Recent evidence suggests that epithelial ovarian cancer (EOC) does not derive from ovarian surface
epithelium but from the tissues of Mullerian origin, particularly from the fallopian tube. HE4, a protein of Mullerian origin,
seems to be promising marker for EOC detection and treatment monitoring. This study was designed to compare
the expression of WFDC2 gene, encoding HE4 protein, in normal tissue of the ovary, fallopian tube and EOC.
The correlation between WFDC2 expression in cancer tissue and serum level of HE4 was additionally measured.
Material and methods: Tumor specimens were obtained from EOC patients during primary surgery before chemotherapy.
Samples of normal ovaries and fallopian tubes were collected from healthy patients operated for other
reasons. Total RNA was isolated from the tissues and relative WFDC2 expression was evaluated by Real Time RTqPCR.
HE4 serum level in cancer patients was measured using COBAS System.
Results: EOC samples were distinguished by much higher WFDC2 expression in comparison to normal ovaries
(p=0.000016). Transcriptional activity of WFDC2 in EOC specimens and in normal fallopian tubes was comparable
(p=1.00). Additionally, lack of correlation between WFDC2 expression in cancer tissue and serum level of HE4
protein in ovarian cancer patients was observed (p=0.3).
Conclusions: High expression of WFDC2 was demonstrated for both, EOC and fallopian tube, as opposed to its
low expression observed in normal ovaries suggesting that EOC is derived from fallopian tube rather than ovary.
Elevated HE4 serum concentration in EOC patients is not correlated with higher gene expression in cancer tissue.Cel pracy: Ostatnie badania sugeruj膮, 偶e rak jajnika (EOC) nie pochodzi z nab艂onka jajnika lecz z tkanek pochodzenia
Mullerowskiego, a najprawdopodobniej z jajowodu. HE4, bia艂ko pochodzenia Mullerowskiego, wydaje
si臋 by膰 obiecuj膮cym markerem raka jajnika. To badanie zosta艂o przeprowadzone, aby por贸wna膰 ekspresj臋 genu
WFDC2 koduj膮cego bia艂ko HE4 w tkance prawid艂owego jajnika, jajowodu oraz raka jajnika. W raku jajnika dodatkowo
zosta艂a oceniona korelacja mi臋dzy ekspresj膮 WFDC2 a st臋偶eniem jego produktu bia艂kowego w surowicy krwi.
Materia艂 i metody: Materia艂 tkankowy zosta艂 pobrany od pacjentek podczas pierwotnej operacji cytoredukcyjnej
raka jajnika. Fragmenty prawid艂owych jajnik贸w i jajowod贸w zosta艂y pobrane od pacjentek operowanych z powodu
mi臋艣niak贸w macicy. Z tkanek zosta艂o wyizolowane ca艂kowite RNA. Za pomoc膮 Real-Time RT-qPCR zosta艂a okre艣lona
ekspresja WFDC2. St臋偶enie bia艂ka HE4 w surowicy krwi pacjentek zosta艂o zmierzone za pomoc膮 systemu
COBAS.
Wyniki: Stwierdzili艣my istotnie wy偶sz膮 ekspresj臋 genu WFDC2 w tkankach EOC ni偶 w tkankach prawid艂owego
jajnika (p=0.000016). Nie stwierdzili艣my natomiast r贸偶nic miedzy ekspresj膮 WFDC2 w jajowodzie oraz w raku jajnika
(p=1.00). Dodatkowo, wykazali艣my brak korelacji mi臋dzy ekspresj膮 tkankow膮 WFDC2 oraz st臋偶eniem HE4
w surowicy krwi u pacjentek z rakiem jajnika. (p=0.3).
Wnioski: Wysoka ekspresja WFDC2 stwierdzona zar贸wno w raku jajnika jak i prawid艂owym jajowodzie w przeciwie艅stwie
do niskiej ekspresji stwierdzonej w jajniku sugeruje, 偶e rak jajnika mo偶e wywodzi膰 si臋 raczej z jajowodu
ni偶 z jajnika. Wysokie st臋偶enie HE4 w raku jajnika nie koreluje z nadekspresj膮 WFDC2 w tkance nowotworowej
Warto艣膰 diagnostyczna HE4 i CA125 w wykrywaniu i r贸偶nicowaniu typu I i II raka jajnika
Objectives: The aim of this study was to assess the sensitivity and specificity of HE4 in detecting and differentiating between types I and II epithelial ovarian cancer (EOC) in comparison with CA125.
Material and methods: We measured HE4 and CA125 serum concentrations in 206 samples taken from patients operated in Gynecologic Oncology Department due to ovarian tumors. Ovarian cancer was confirmed in 89 cases divided into type I and type II. 52 healthy patients without any gynecological disease formed the control group. The sensitivity and specificity for type I and type II EOC detection and differentiating between both types was evaluated
for HE4 and CA125.
Results: The HE4 and CA125 serum concentrations were significantly higher in type II than in type I EOC (p=0.008696, p=0.000243 respectively).The HE4 and CA125 sensitivity for type I and benign tumors differentiation was 63.16% for both of them and specificity was 87.29% vs 67.89% respectively. For CA125 these differences did not reach statistical significance. The HE4 sensitivity and specificity for type II and benign tumors differentiation were 87.14% and 96.61%, respectively, and for CA125 these values were 82.86% and 94.07%, respectively.
Conclusions: Pretreatment analysis of HE4 serum concentration is superior to CA125 in differential diagnosis of ovarian cancer subtypes (I and II). HE4 is superior to CA125 in detecting ovarian cancer type II. Neither HE4 nor CA125 is an effective diagnostic tool for type I ovarian cancer detection. A new highly specific and highly sensitive tumor marker for type I EOC is needed.Cel pracy: Celem pracy by艂o okre艣lenie czu艂o艣ci i swoisto艣ci bia艂ka HE4 w wykrywaniu i r贸偶nicowaniu typu I i II raka jajnika (EOC) w por贸wnaniu z CA125.
Materia艂 i metody: St臋偶enia HE4 oraz CA125 zosta艂y zmierzone w pr贸bkach surowicy krwi pobranej od 206 pacjentek operowanych w Klinice Onkologii Ginekologicznej z powodu guz贸w jajnika. Rak jajnika zosta艂 potwierdzony w 89 przypadkach podzielonych na typ I i II EOC. Grup臋 kontroln膮 utworzy艂y 52 zdrowe pacjentki bez schorze艅 ginekologicznych. Zosta艂a okre艣lona czu艂o艣膰 i swoisto艣膰 HE4 oraz CA125 w wykrywaniu oraz r贸偶nicowaniu typu I i II EOC.
Wyniki: St臋偶enia HE4 i CA125 by艂y istotnie wy偶sze w typie II ni偶 w typie I EOC (p=0,008696, p=0,000243). Czu艂o艣膰 w r贸偶nicowaniu typu I EOC i guz贸w niez艂o艣liwych wynosi艂a 63,16% dla obydwu marker贸w, HE4 wykaza艂o swoisto艣膰 87,29% a CA125 67,89%. Dla CA125 nie stwierdzono jednak istotno艣ci statystycznej. Czu艂o艣膰 i swoisto艣膰 HE4 w r贸偶nicowaniu typu II EOC i zmian niez艂o艣liwych wynosi艂a 87,14% i 96,61%, natomiast dla CA125 wynosi艂a
82,86% i 94,07%.
Wnioski: Przedoperacyjne okre艣lenie st臋偶enia HE4 ma wi臋ksz膮 warto艣膰 w r贸偶nicowaniu typu I i II raka jajnika ni偶 CA125. HE4 jest lepszym markerem w diagnostyce typu II raka jajnika. 呕aden z badanych marker贸w nie ma zadowalaj膮cej czu艂o艣ci i swoisto艣ci w wykrywaniu typu I EOC. Do diagnozowania tego typu nowotworu jest potrzebny nowy wysoce czu艂y i swoisty marker