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PubMed2006

Green luminescence band in ZnO: fine structures, electron-phonon coupling, and temperature effect.

The green emission band of ZnO has been investigated by both experimental and theoretical means. Two sets of equally separated fine structures with the same periodicity (close to the longitudinal optical (LO) phonon energy of ZnO) are well resolved in the low-temperature broad green emission spectra. As the temperature increases, the fine structures gradually fade out and the whole green emission band becomes smooth at room temperature. An attempt to quantitatively reproduce the variable-temperature green emission spectra using the underdamped multimode Brownian oscillator model taking into account the quantum dissipation effect of the phonon bath is done. Results show that the two electronic transitions strongly coupled to lattice vibrations of ZnO lead to the observed broad emission band with fine structures. Excellent agreement between theory and experiment for the entire temperature range enables us to determine the dimensionless Huang-Rhys factor characterizing the strength of electron-LO phonon coupling and the coupling coefficient of the LO and bath modes.

Journal Article↗

PubMed2006

Long-lived coherent oscillations of the femtosecond transients in cyanobacterial photosystem I.

The pulsed excitation of electronic levels coupled to specific nuclear modes by a 26 fs laser pulse at 706 nm creates a wavepacket in the nuclear space of photopystem I (PS I) of Synechocystis sp. strain PCC 6803 both in the ground state and in the one-exciton manifold. Fourier transform of transient decay curves shows several low frequency peaks. The most prominent Power Spectral Density (PSD) peaks are at omega = 49 cm(-1) and omega = 88 cm(-1). The peculiarity of the coherent wavepacket in the PS I of S. sp. strain PCC 6803 is the unique, long-lived 49 cm(-1) and 88 cm(-1) oscillations with decay times up to 10 ps. It was suggested that such a long-lived coherence is determined by a contribution of the ground state wavepacket. The dependence of these two PSD peaks on the probe wavelength resembles the profile of the transient absorption spectra of PS I. The pump-probe signal in the Soret region reflects the dynamics of the ground state wavepacket created by pulsed excitation of the Q(y)-band. It was shown that the multimode Brownian oscillator model allows a quantitative fit of the oscillatory patterns of the pump-probe signal to be obtained.

Lasers↗

PubMed2005

Ultrafast dynamics of pyrrolidinium cation ionic liquids.

We have investigated the ultrafast molecular dynamics of five pyrrolidinium cation room temperature ionic liquids using femtosecond optical heterodyne-detected Raman-induced Kerr effect spectroscopy. The ionic liquids studied are N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide P14+/NTf2-), N-methoxyethyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide P1EOE+/NTf2-), N-ethoxyethyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide P1EOE+/NTf2-), N-ethoxyethyl-N-methylpyrrolidinium bromide P1EOE+, and N-ethoxyethyl-N-methylpyrrolidinium dicyanoamide P1EOE+/DCA-). For comparing dynamics among the five ionic liquids, we categorize the ionic liquids into two groups. One group of liquids comprises the three pyrrolidinium cations P14+, P1EOM+, and P1EOE+ paired with the NTf2- anion. The other group of liquids consists of the P1EOE+ cation paired with each of the three anions NTf2-, Br-, and DCA-. The overdamped relaxation for time scales longer than 2 ps has been fit by a triexponential function for each of the five pyrrolidinium ionic liquids. The fast ( approximately 2 ps) and intermediate (approximately 20 ps) relaxation time constants vary little among these five ionic liquids. However, the slow relaxation time constant correlates with the viscosity. Thus, the Kerr spectra in the range from 0 to 750 cm(-1) are quite similar for the group of three pyrrolidinium ionic liquids paired with the NTf2- anion. The intermolecular vibrational line shapes between 0 and 150 cm(-1) are fit to a multimode Brownian oscillator model; adequate fits required at least three modes to be included in the line shape.

Cations↗

PubMed2006

Chemoradiotherapy of anal cancer is feasible in elderly patients: treatment results of mitomycin-5-FU combined with radiotherapy at Helsinki University Central Hospital 1992-2003.

The number of elderly patients with cancer is steadily increasing in developed countries and their treatment is a growing challenge for oncological departments. Anal cancer is the first tumour in which chemoradiotherapy with the intent of organ preservation has largely replaced surgery and is an interesting model of modern multimodal oncological treatment. At the Department of Oncology of the Helsinki University Central Hospital we have treated all patients irrespective of age following the same guidelines if there have been no specific contraindications on the basis of intercurrent diseases. The results suggest that the chemoradiotherapy protocol used in the treatment of anal cancer is reasonably well tolerated in elderly patients and the tumour control is comparable to those achieved in younger patients. After successful cancer therapy the life expectancy in these patients can be very long.

Adult↗

PubMed2006

Generating controllable atom-light entanglement with a Raman atom laser system.

We introduce a scheme for creating continuous variable entanglement between an atomic beam and an optical field, by using squeezed light to outcouple atoms from a Bose-Einstein condensate via a Raman transition. We model the full multimode dynamics of the atom laser beam and the squeezed optical field and show that, with appropriate two-photon detuning and two-photon Rabi frequency, the transmitted light is entangled in amplitude and phase with the outcoupled atom laser beam. The degree of entanglement is controllable via changes in the two-photon Rabi frequency of the outcoupling process.

Journal Article↗

PubMed2004

Multimode shunt damping of piezoelectric smart panel for noise reduction.

Multimode shunt damping of piezoelectric smart panel is studied for noise reduction. Piezoelectric smart panel is a plate structure on which a piezoelectric patch is attached with an electrical shunt circuit. When an incidence sound is impinged on the panel structure, the structure vibrates and the attached piezoelectric patch produces an electrical energy, which can be effectively dissipated as heat via the electrical shunt circuit. Since the energy dissipation strongly depends on the vibration mode of the panel structure, many patches are required for multiple vibration modes. Instead of using multiple piezoelectric patches, a single piezoelectric patch is used in conjunction with a blocked shunt circuit for multimode shunt damping. Modeling, shunt parameter tuning, and implementation of the blocked shunt circuit along with an acoustic test of the panel are explained. A remarkable reduction of the transmitted noise was achieved for multiple modes of the panel. Since this technology has many merits in terms of compactness, low cost, robustness, and ease of installation, practical applications in many noise problems can be anticipated.

Acoustics↗

PubMed1998

Ultrafast solvation dynamics explored by femtosecond photon echo spectroscopies.

Chemical reaction and optical dynamics in the liquid phase are strongly affected by specific solute-solvent interactions. The dynamical part of this coupling leads to energy fluctuations. The associated energy gap dynamics can be probed by using various nonlinear optical spectroscopies. We discuss various forms of photon echo--time-integrated, time-gated, and heterodyne-detected photon echo--as well as Fourier transform spectral interferometry. It is shown that for solutions of the dye molecule DTTCI, a system-bath correlation function can be acquired that provides a quantitative description of all (non)linear spectroscopic experiments. The deduced correlation function is projected onto the multimode Brownian oscillator model, which allows for a physical interpretation of the multiple-time correlation function and a determination of the spectral density relevant to the solvation process. The following applications of photon echo to condensed phase dynamics are discussed: enhanced vibrational mode suppression, Liouville pathways interference, and dynamical Stokes shift. Recent results of echo-peak shift experiments on the hydrated electron are also presented. The review concludes that photon echo should be useful as a novel tool to explore transition state dynamics.

Journal Article↗

PubMed1980

A multimodal approach to elimination of stuttering.

Various approaches have been used in the treatment of stuttering. However, none of these approaches have been systematically incorporated via a multifaceted treatment program for the elimination of this disorder. The following case of a 15-yr.-old stutterer is presented to illustrate Lazarus' Multimodal Behavior Therapy Model, which is proposed to integrate various procedures whose singular effectiveness has been demonstrated.

Adolescent↗

PubMed1982

Treatment of drug and alcohol abuse in spinal cord injury veterans.

An innovative program has been developed at the VAMC in Long Beach, California, for the treatment of spinal cord injured veterans who are also drug or alcohol dependent. The program employs a multimodal therapeutic community model in which patients progress through successive phases, each involving increasing responsibilities and privileges. This presentation deals with the design and results of a research instrument created for the evaluation of the Drug Dependence Treatment Program (DDTP). The instrument is a posttreatment, parameter study of the multidisciplinary program. The questions asked of former patients of the DDTP were designed to investigate intrapersonal and interpersonal integration, both directly and discreetly. Questions were asked regarding arrests, length of time at domicile, hospital admissions, and use of drugs or alcohol--specifically, present use of the substance misused at the time of admission to treatment. Life-style stability or change was investigated and confirmed with collateral support, as evidenced by comparing information drawn from the 3-month period prior to admission to the treatment program with the 3-month period immediately preceding administration of the instrument. Results from the preliminary data support substantial gain in individual patient psychological and social integration. It is significant that 56% of former patients were not using treatment admission drugs.

Adult↗

PubMed1997

Germ cell tumours---local perspectives on a curable cancer.

Germ cell tumours are among the most curable solid cancers and have become a model for the multimodality approach in oncology. The experience of two institutions in Hong Kong involving 149 Chinese patients with testicular germ cell tumours and 10 patients with mediastinal germ cell tumours was reviewed and the overall results were found to be comparable with the global experience. Treatment strategies suitable for the local population are discussed. The earlier identification of patients with metastatic non-seminomatous germ cell tumours who have a poor prognosis, may be important in selecting patients for more intensive treatment such as high dose chemotherapy. With mediastinal germ cell tumours, survival is poorer and improved treatment results may only be possible with increased understanding of the biological abnormalities involved. An integrated multimodality approach to the diagnosis and treatment of this disease is vital to attain optimal management. For these reasons, it is recommended that all patients with germ cell tumours be referred to cancer centres where cross-specialty expertise and experience are available to manage these patients.

Journal Article↗

PubMed1988

Computer graphics in medicine: a survey.

Increased interest is presently given to three-dimensional (3-D) medical applications due to simultaneous emergence of high-resolution imaging systems and computer graphics techniques. This paper intends to present a survey of this field together with discussion and prospective views. The general framework is composed of six parts: data acquisition and preprocessing, polygonal object representation, voxel description, system architecture, medical applications, and prospects. Data base acquisition includes characterization of imaging modalities and medical specificity. Preprocessing schemes are directed to improvements (filtering), windowing, and spatial anisotropy (linear or spline interpolation). The two following sections are devoted to descriptions of the main object representations. Particular emphasis is given to optimal contour approximation, surface triangulation, mathematical surfaces on one hand, and cuberille and voxel representations on the other. Display capabilities--hidden surface removal, surface normal shading, structure enhancement--and data base structuration--hierarchical and nonhierarchical (graph and tree encoding)--are, respectively, described. An overview of 3-D systems is further given (Section V), and features of medical applications are reviewed and gathered in basic functionalities, surgery, and radiotherapy specifications (Section VI). The last section provides some prospective views on reconstruction from a few projections, model-guided labeling, multimodality image overlay, and local image network. Some of these issues are illustrated by examples of 3-D images.

Computer Graphics↗

PubMed1987

Management of primary stage D prostatic cancer.

Androgen withdrawal rarely if ever results in a cure of prostatic carcinoma. Thus, if the object of therapy is to cure rather than palliate, it is necessary for us to alter our strategem so as to trick the prostatic cancer cells into dying while sparing the host. Data has been presented that suggest that tumor cell heterogeneity and the preexistence of populations of cells resistant to androgen withdrawal are responsible for the failure of hormonal therapy. Additionally, the use of androgen withdrawal as a single mode of therapy may actually induce a more rapid emergence of cells resistant to chemotherapeutic intervention by increasing the genetic instability of the tumor population. Assuming that a tumor is composed of a heterogeneous population of cells and the institution of unimodal therapy will exert a destabilizing influence on the tumor, the logical therapy for disseminated disease would be multimodal therapy. Animal models suggest that the most effective therapy for disseminated disease would be a combination of androgen withdrawal and cytotoxic chemotherapy instituted as early as possible when the number of cells capable of division, stem cells, is at minimum. Whether or not early, sequential withdrawal, repletion, withdrawal of hormones to synchronize the tumor cell cycle and increase the growth fraction of the tumor will have any beneficial effects remains to be determined. This form of androgen priming should be safer than in patients with hormonally refractive disease since LHRH initially stimulates testosterone production without any significant irreversible sequelae. Although the above therapeutic logarithms may prove to have no therapeutic advantage over androgen withdrawal alone, it certainly seems a good starting point for a change in our therapeutic concepts. Only by adopting new approaches based upon what we know about tumor biology can we hope to impact on the current dismal prognosis.

Combined Modality Therapy↗

PubMed2000

Models of the posterior parietal cortex which perform multimodal integration and represent space in several coordinate frames.

Many neurons in the posterior-parietal cortex (PPC) have saccadic responses to visual and auditory targets. The responses are modulated by eye position and head position. These findings suggest that PPC integrates multisensory inputs and may provide information about saccadic targets represented in different coordinate frames. In addition to an eyecentered output representation, PPC may also project to brain areas which contain head-centered and body-centered representations of the space. In this report, possible coordinate transformations in PPC were examined by comparing several sets of models of PPC, each having different representations in the output layer: (i) an eye-centered map only; (ii) a head-centered map only; (iii) an eye-centered map and a head-centered map; and (iv) an eye-centered map, a head-centered map, and a body-centered map. These output maps correctly encoded saccades to visual and auditory targets through training. The units in the hidden layers of the models exhibited the following properties: (1) The units had gain fields (GFs) for eye position, and also for head position if the model had a body-centered output representation; (2) As the result of the GF and the nonlinear activation function of the units, the hidden layers often employed "intermediate" coding, e.g., the hidden units coded targets partially in eye-centered coordinates and, partially, in head-centered coordinates; (3) Different types of coordinate transformations in these models were carried out by different relationships between the receptive fields (RFs) and the GFs of the hidden units; and (4) The properties of PPC neurons are in better accordance with the hidden units of the models that had multiple-output representations than the models that had only one single-output representation. In conclusion, the results show that the GF is an effective mechanism for performing coordinate transformations. The models also suggest that neurons with intermediate coding are to be expected in the process of coordinate transformations.

Algorithms↗

PubMed2026

Large language models in bioinformatics: a comprehensive survey.

The emergence of foundation models with trillion-level parameters has redefined the landscape of artificial intelligence. Various fields are developing their own large-scale models, which can solve many problems within the field and improve work efficiency. Biological large-scale models are a cross-disciplinary research field that combines mathematics, computer science, and biology, aiming to simulate and understand the structure, function, and dynamic changes of biological systems through the establishment of complex computational models. This field covers multiple levels such as biological pathways, population dynamics, protein folding, etc., providing us with tools for deep exploration of the mysteries of life and applications in medicine, ecology, and other fields. This article reviews the background and research status of biological large-scale models, and discusses future directions. Large language models (LLMs) and other large-scale foundation models have rapidly advanced in recent years, enabling powerful representation learning and generation across text, sequences, and multimodal data. In bioinformatics and biomedicine, these models are increasingly used to analyze genomic sequences, infer protein properties and structures, support drug discovery, and integrate heterogeneous biomedical evidence. This survey reviews the basic principles of LLMs and summarizes representative applications in (i) gene and genome sequence analysis, (ii) protein structure and function prediction, and (iii) drug design, including virtual screening and personalized medicine. We also discuss emerging multi-model modeling approaches, as well as key challenges such as data quality and privacy, interpretability, generalization to new organisms and tasks, and responsible deployment in health-related settings. Finally, we outline future directions for developing reliable, scalable, and explainable bioinformatics foundation models.

bioinformatics↗

PubMed2026

Dual-Reporter Gene-Based Multimodal Imaging for Tracking Mesenchymal Stem Cells in Diabetic Skin Wound Repair.

BACKGROUND: Diabetic foot ulcer (DFU) is a clinically challenging complication characterized by poor healing outcomes, and conventional therapies provide limited benefit. Mesenchymal stem cell (MSC) transplantation offers a promising strategy for DFU repair. However, the low survival of transplanted MSCs in the hostile wound microenvironment, coupled with the lack of real-time, non-invasive methods to track these cells in vivo, severely hampers their therapeutic efficacy and clinical translation. METHODS: We engineered MSCs to co-express a dual reporter system comprising near-infrared fluorescent protein (iRFP) and ferritin heavy chain (FTH1). These modified cells were then integrated with a fibrin glue (FG) scaffold to create a unified platform that supports both multimodal imaging and therapeutic function within skin wounds. First, FTH1 overexpression enhances the antioxidant capacity of MSCs, while the FG scaffold provides structural support; this combination enhances cell survival and retention. Second, the iRFP/FTH1 dual reporter enables near-infrared fluorescence imaging and MRI-based localization, establishing a multimodal platform for real-time cell tracking. RESULTS: In a full-thickness skin defect model in diabetic mice, multimodal imaging revealed that transplanted cells persisted in the wound area for approximately seven days. Treatment with iRFP/FTH1-MSCs/FG significantly accelerated wound closure and promoted hair follicle regeneration and angiogenesis. Additionally, local iron deposition resulting from FTH1 expression enhanced fibroblast migration and collagen synthesis, further facilitating extracellular matrix remodeling. Mechanistic studies demonstrated that this therapy drives macrophage polarization toward the anti-inflammatory M2 phenotype and activates the PI3K-AKT-VEGF signaling pathway. These complementary effects synergistically enhance tissue regeneration and systematically improve diabetic wound healing. CONCLUSIONS: Collectively, this multimodal stem cell-scaffold system effectively integrates dynamic cell tracking with stem cell therapy during skin wound repair. It addresses a critical technical gap in visualizing stem cells within the wound microenvironment and provides valuable methodological and theoretical foundations for optimizing regenerative strategies for diabetic skin wounds.

Animals↗

PubMed2004

Multimodal imaging in the elastase-induced aneurysm model in rabbits: a comparative study using serial DSA, MRA and CTA.

BACKGROUND AND PURPOSE: The elastase-induced aneurysm model in rabbits has proved to be suitable for testing new endovascular occlusion devices. The purpose of this study was to evaluate different imaging modalities for the depiction of anatomy and size of elastase-induced aneurysms and for serial follow-up imaging. MATERIALS AND METHODS: Elastase-induced aneurysms were created in eight Chinchilla bastard rabbits by endoluminal incubation of porcine elastase. Serial imaging was performed using intravenous DSA (IVDSA), contrast-enhanced MRA (CEMRA), and time-of-flight MRA (TOF) 14 days, 4 weeks and 3 months after aneurysm creation. Intraarterial DSA (IADSA) and CT angiography (CTA) were performed after 3 months. Aneurysm size and geometry (height H, width W, neck width N) were compared. RESULTS: On IVDSA after two weeks mean aneurysm height was 6.2 mm (range 2.8 - 11.0 mm), mean aneurysm width was 2.8 mm (range 2.0 - 4.2 mm) and mean aneurysm neck width was 2.7 mm (range 2.0 - 4.2 mm). We did not observed any statistically significant change in aneurysm dimensions during follow-up at 4 weeks (CEMRA: H: 5.4, W: 2.4, N: 2.4; TOF: H: 5.7, W: 2.4, N: 2.7) and 3 months (CEMRA: H: 5.8, W: 2.6, N: 2.6; TOF: H: 6.9, W: 2.8, N: 3.0). Aneurysm dimensions could be best seen on IADSA (H: 6.2, W: 3.0, N: 2.7) with good correlation to CTA (r = 0.94; H: 6.1, W: 2.8, N: 2.6), CE-MRA (r = 0.92), and TOF (r = 0.97). TOF was superior to CEMRA in delineating the aneurysm wall. CONCLUSIONS: Serial imaging using MRA, CTA or intravenous and intraarterial angiography is feasible in the elastase-induced aneurysm model. Contrast-enhanced MRA, TOF-MRA and CTA showed good correlation to IADSA and are all suitable for non-invasive pretherapeutic measurement of aneurysm size.

Angiography↗

PubMed1983

[Inpatient behavior therapy of depression--a multimodal approach in clinical practice].

Using a reinforcement-oriented model of depression, we applied a multimodal approach of behavior therapy in clinical setting. We modified the self-control-group-therapy of psychoreactive depression, developed by Fuchs und Rehm (1977) in order to reach applicability for inpatients of psychiatric hospital. Operant techniques, social skills training, self-control-techniques, and the cognitive techniques developed by Beck (1979) were used. In contrast to Becks cognitive therapy we emphasized both the motivational aspect of depression and the aspect of self-regulation and self-modification too. There was not only the therapist trying to change behavior, thinking, and feeling of the patient by cognitive techniques. The patient himself tried to develop cognitive and behavior coping strategies. The treatment of patients with severe depression in an early stage was controlled by the therapist, later on they learned to control themselves. A central point of the concept of self-modification is teaching well founded knowledge of behavior analyses to the patient. Self-modification is not very efficient without, and the patient's motivation to work on his own therapy is elevated significantly. In some cases we continue this form of therapy after the patient's leaving the hospital up to three months.

Adult↗

PubMed2026

Deep learning-based multimodal pathogenomics integration for precision cancer prognosis.

BACKGROUND: Recent studies have revealed valuable prognostic insights in haematoxylin and eosin (H&E)-stained histological sections and transcriptomic profiles, suggesting potential applications in machine learning. However, existing methods lack sufficient intra- and inter-modal interactions, and face challenges in clinical validation due to incomplete multimodal data. METHODS: We proposed PathoGems (PathoGenomics-based integrative survival prediction), a weakly-supervised, interpretable multimodal learning framework that integrates histology and genomic profiles for precise cancer prognosis prediction. To evaluate the robustness of PathoGems, we initially curated a dataset of 1965 cases across four cohorts from The Cancer Genome Atlas (TCGA), including breast, colorectal, glioblastoma, and esophageal cancers. For external validation, PathoGems was further evaluated on four independent cohorts, consisting of 76 breast cancer and 41 esophageal squamous cell carcinoma cases from Zhejiang Cancer Hospital, as well as 102 colorectal cancer and 58 glioblastoma cases from the Clinical Proteomic Tumor Analysis Consortium (CPTAC). RESULTS: PathoGems effectively stratified patients into favorable and unfavorable risk groups, revealing significant differences in histological patterns, genomic features, and overall survival (log-rank test, p < 0.05). Moreover, the model’s predictions are further supported by visualization and transcriptomic analysis, enhancing interpretability and reliability. CONCLUSIONS: By fusing histological and clinicogenomic multimodal models, PathoGems will provide a solid foundation for developing an innovative tool that aids clinicians in making informed decisions and selection personalized treatment strategies for cancer patients.

Humans↗