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A new technique is proposed, verified, and described for measuring photosensitivity spectra of semiconductor materials and devices in the wavelength range of 200–4100 nm utilizing an innovative setup termed “Polychromator” with a system of cut-off optical filters that provide a sharp edge of the spectrum of radiation impinging on the sample. The measured value, referred to as selective integral photosensitivity (SIPhS), is calculated for the particular subbands of the spectrum taking into account the radiation power. Certain IR spectral characteristics, measured with a monochromator, are provided for comparison. It is shown that the presented “Polychromator” measurement data do not contradict these results, and in fact, complement them. The reliability of the method is demonstrated by three types of test photodiodes fabricated using three base materials: 1) B+ ion-implanted n-Si; 2) InGaAs/InP; and 3) undoped AlGaN/GaN heterostructures. The selected materials and the devices made therefrom differ in the nature of photoresponse revealed in the various wavelength ranges. This allows for comprehensively describing the methodology. The information gained using this method as well as its advantages and ways of improving the setup are discussed.

Esophageal carcinoma is the seventh most common cancer and the sixth most lethal cancer worldwide. There are two main histological types of esophageal carcinoma: adenocarcinoma (AC) and squamous cell carcinoma (SCC). Both histological types are more common in males than females. Menopause is an independent risk factor for esophageal cancer while usage of hormonal therapy (estrogen plus progesterone) is associated with a lower risk of esophageal SCC in postmenopausal women. Gender differences have an impact on SCC incidence, however, it is unclear if gender has a prognostic value for survival. The present case report describes a young woman who developed SCC of the esophagus. The disease was diagnosed in the locally advanced stage. Definitive chemo-radiotherapy induced complete response. These findings might suggest that in young women esophageal SCC may have a better prognosis.

We study climate and macroprudential policies in an economy with financial frictions. Using a dynamic stochastic general equilibrium model featuring both a pollution market failure and a market failure in the financial sector, we explore transition risk – whether ambitious climate policy can lead to macroeconomic instability. It can, but the risk can be alleviated through macroprudential policies – taxes or subsidies on banks’ assets. Then, we explore efficient climate and macroprudential policy in the long run and over business cycles. The presence of financial frictions affects the steady-state value and dynamic properties of the efficient carbon tax. Macroprudential policy alone, without a carbon tax, is not very effective at addressing the pollution externality. Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

This manuscript presents an ad-hoc methodology for the assessment of the vulnerability of buildings to be applied in Georgia where such assessment is included in the management risk approach designed to work at the national level.

Background: COVID-19 pandemic created major challenges in cancer care. Studies have shown increased risk for COVID-19 infectivity, severe disease and death in patients with cancer. Cancer centers worldwide adapted by modifying and often delaying treatment to minimize contact with patients. Methods: To provide safe and uninterrupted care for patients, a home care program was created for patients with prostate cancer at Acad. F. Todua Medical center. Men with locally advanced or metastatic prostate cancer (MPC) receiving androgen deprivation therapy (ADT) were enrolled. Patients and their caretakers were instructed on gonadotropin-releasing hormone (GnRH) subcutaneous injections (SQ) for home administration. Monthly at home laboratory testing and virtual consultations with medical oncologists every 1-3 months were arranged. Results: A total of 52 patients were enrolled during the period of March 2020 – March 2021. All men were White and had ECOG 0/1. The mean age was 71 [±6.3 y] years. Sixteen (31%) patients had stage IIIB PC and 36 (69%) patients had stage IV disease. Stage IIIB patients were receiving adjuvant ADT with SQ Goserelin Acetate 10,8mg every 8 weeks and bicalutamide 50mg daily for two weeks after definitive local treatment. Thirty-one (86%) patients had hormone sensitive metastatic PC and were receiving SQ Goserelin Acetate 10.8mg (28) every 8 weeks or SQ Leuprolide Acetate 22,5mg every 8 weeks (3) with 2 weeks of Bicalutamide 50mg daily. Five (14%) patients had castration resistant (CR) PC and were receiving SQ Goserelin Acetate 10,8mg every 8 weeks with Enzalutamide 160mg daily. Thirty-three (63%) patients had Gleason’s score of 8/9. All patients were compliant with home injections, laboratory tests and virtual physician visits. Thirty-nine (75%) patients administered injections by themselves. Forty-two (80%) patients had PSA reduction >50%. Ten (20%) patients had disease progression and required clinic visits for investigations. Median time to progression was 12 months. Only 1 (2%) patient acquired COVID-19 infection, was hospitalized and died of respiratory failure. Conclusions: At home ADT with appropriate patient/caregiver education and close follow up may be safe for patients with PC during the COVID-19 pandemic. Legal entity responsible for the study: Acad. F. Todua Medical Center Department of Oncology and Hematology. Funding: Has not received any funding. Disclosure: All authors have declared no conflicts of interest.

Background: Cancer patients are particularly vulnerable to the deleterious consequences of lockdown and social distancing. The psychosocial effects of the COVID-19 pandemic on this group are still unknown. Young female cancer patients need extra support in this unique situation. We want to explore if their quality of life could be affected by online group psychotherapy during the Covid-19 pandemic. Methods: An online survey, EORTC QLQ-C30 was administered to a cohort of young gynecologic cancer patients. The questionnaire also incorporated questions about their specific diagnoses and current treatment. Inclusion criteria included female patients aged 18-45 who were diagnosed with cancer during the last 5 years. We asked selected patients to fill the survey twice, before and after group psychotherapy sessions. Online group psychotherapy was conducted for 3 consecutive months, three times per week, using the interactive ZOOM platform. Results: Total of 25 patients aged 18-45 were included in the study, 17 patients were breast and 8 were cervical cancer patients. 52% were receiving hormonal therapy, remaining patients were receiving chemotherapy, radiation therapy targeted treatment, or was on follow-up. The scores of physical (82 vs 79.5) role (47.5 vs 51.6) emotional (73.8 vs 80) cognitive (47.5 vs 51.6) social functioning (47.5 vs 51.6) were different between pre and post pschysotherapy sessions. In breast cancer group pre and post group psychotherapy results were significantly different with PF -p=0.0035, RF - p=0.0035, EF - p=0.0073, CF - p=0.0035, SF p=0.0035 symptom scales/items - p=0.0035. In cervical cancer group pre and post group psychotherapy results were not significantly different;PF -p=0.4435, RF - p=0.3394, EF - p=0.4435, CF - p=0.3394, SF - p= 0.3394 symptom scales/items - p= 0.4435. Conclusions: Our results show that young breast cancer patients' QoL can be positively affected by online group psychotherapy, but outcomes were not the same in the cervical cancer group. More research and larger sample size are needed for a better interpretation of results. Legal entity responsible for the study: The authors. Funding: Has not received any funding. Disclosure: All authors have declared no conflicts of interest.

For specific modification of the fundamental optical and photoelectrical properties of silicon transparent for wavelengths beyond 1.1μm, boron ions have been implanted into n-type wafers at doses of 1 х 1013 cm-2–1 х 1015 cm-2 followed by annealing at 900 °C and 1000 °C (20 min). The IR reflection spectra, Raman spectroscopy and scanning electron microscopy data have been compared with the photosensitivity spectra (1.4–2.2 μm) and with the integrated photoresponse in the IR (1.0–4.1 μm) and UV (0.25–0.4 μm) regions. These studies allow for materials engineering to obtain new data on the influence of defect formation on the optical properties of the material and to evaluate the technological conditions for practical application of the modified material.

Background Chemotherapy (chemo)-induced damage of hematopoietic stem and progenitor cells (HSPC) causes multi-lineage myelosuppression. Current supportive therapies are lineage specific and administered after damage has occurred. T, a highly selective, reversible CDK4/6 inhibitor and first-in-class myelopreservation agent, preserves HSPCs during chemotherapy, improving its safety and tolerability. This trial (NCT03041311) studied the benefits of T in ES-SCLC patients receiving 1L chemo + atezolizumab (A). Methods This placebo (P)-controlled, double-blind, Ph2 study randomized (1:1) chemo-naive ES-SCLC pts with adequate organ function, ECOG 0-2, and no symptomatic brain mets, to T or P with etoposide/carboplatin/A (ECA) for four induction cycles followed by maintenance (A). Prophylactic growth factors were prohibited in cycle 1; otherwise standard supportive care was allowed. Prespecified lineage-specific endpoints assessed the effect of T on myelosuppression. Tumor response was assessed using RECIST v1.1. FACT-L and FACT-An were evaluated. Results T + ECA was well tolerated with fewer ≥ G3 AEs in T (62% overall; 50% any drug related) vs P (87%; 74%), primarily due to less heme toxicity. T improved ANC, RBC measures and SOC interventions (Table). T also delayed time to deterioration in some PRO functioning domains and anemia symptoms. T did not affect chemo efficacy as measured by ORR and PFS; OS will be presented. Table: 1742PD . Parameter, n [1] ECA + P N = 53 ECA + T N = 54 Adjusted 1-sided P- value Mean Duration (d) G4 ANC in Cycle 1[2] 4 0 Pts w G4 ANC* 26 (49%) 1 (2%) Dose reductions (per 100 cycles) ǂ 8.5 2.1 0.0195 Pts w RBC transfusions ≥ week 5* 11 (21%) 7 (13%) 0.1335 Pts w G-CSF Admin* 25 (47%) 16 (30%) 0.0686 [1] Data presented as proportion (*) or event rate (ǂ) [2] Surrogate for febrile neutropenia Conclusions Addition of T improves safety/tolerability of chemo as shown by statistically significant and clinically meaningful improvement in myelosuppression endpoints, reduction of chemo side effects, and SOC interventions and no detriment to anti-tumor efficacy. These data confirm the myelopreservation benefits of T seen in another 1L ES-SCLC trial (NCT02499770). Clinical trial identification GIT28-05: NCT03041311, EudraCT2017-000358-20. Legal entity responsible for the study G1 Therapeutics, Inc. Funding G1 Therapeutics, Inc. Disclosure D. Daniel: Research grant / Funding (institution): G1 Therapeutics; Research grant / Funding (institution): ER Squibb & sons; Research grant / Funding (institution): AstraZeneca; Research grant / Funding (institution): Boehringer Ingleheim; Research grant / Funding (institution): Genentech; Research grant / Funding (institution): Eli Lilly and Company; Research grant / Funding (institution): Novartis; Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): Celgene; Research grant / Funding (institution): Roche. D. Spigel: Advisory / Consultancy, Research grant / Funding (institution): Genentech/Roche; Research grant / Funding (institution): G1 Therapeutics. J. Jaal: Advisory / Consultancy, Research grant / Funding (institution): AstraZeneca; Advisory / Consultancy: Boehringer Ingelheim. L. Hart: Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: G1 Therapeutics. K.D. Koynov: Honoraria (self), Honoraria (institution), Travel / Accommodation / Expenses: Roche; Honoraria (institution): Boehringer Ingelheim; Honoraria (institution): servier; Honoraria (institution): Novartis; Honoraria (institution): Merck; Honoraria (self), Honoraria (institution), Travel / Accommodation / Expenses: MSD; Honoraria (institution): Bayer; Honoraria (self), Honoraria (institution), Travel / Accommodation / Expenses: Eli Lilly; Honoraria (self), Honoraria (institution), Travel / Accommodation / Expenses: Pfizer; Honoraria (self), Honoraria (institution), Travel / Accommodation / Expenses: Astelas; Honoraria (self), Honoraria (institution), Travel / Accommodation / Expenses: Amgen; Honoraria (institution): Intellect Pharma; Travel / Accommodation / Expenses: AstraZeneca. Z.(. Yang: Full / Part-time employment: G1 Therapeutics. S.G. Wolfe: Full / Part-time employment: G1 Therapeutics. R. Malik: Full / Part-time employment: G1 Therapeutics. S.R. Morris: Full / Part-time employment: G1 Therapeutics. J.M. Antal: Full / Part-time employment: G1 Therapeutics. All other authors have declared no conflicts of interest.

The balm “Graal” (BG) was created within the limits of transnational program “Chernobil Help”. It includes the water-spirit secretion pressed out from the feed-curative plants of Caucasus as well as mountain honey, pollen of the Georgian beer flower and the red wine made from the vine of unique bread. The balm is registrated in the Republics of Ukraine and Byelorussia as a radioprotective Means for preventive inspection and medical treatment of radial injuri. The results was of the balm research on antinarcotic and antialcoholic action is represented in the Article, which was held in the medical centre of radiology in Obninsky city of Russian Federation. In experiments on adult mice and rats it is shown, that radioprotective balm “Graal” (the nonalcoholic concentrate) is effective means for preventive maintenance and treatment of various forms of medicinal dependence (alkoholism, a narcotism). In various tests of conditioned reflexive training, it has been shown, that BG considerably reduces amnestic and narcotic action of ethanol. Natural BG (spirit-including) caused considerably smaller changes in behaviour of animals, rather than equivalent volume of the pure spirit contained in balm. Regular introduction BG by an animal improved the general physical condition of animals and raised their serviceability without effects of an exhaustion, characteristics for other neurostimulators.

Concentrated photovoltaic (CPV) is an important player in R&D and industrial technologies for cost-effective large-scale power plants. The developers' efforts are aimed at increasing the solar cell efficiency and improving optical concentrators to reduce the cost/W. We have proposed an innovative optical concentrator concept based on lenses and reflectors. In the present work an optimized version of the concentrator design is described. Theoretical studies have shown a number of advantages of the proposed innovation - concentration ratio 1000x and more, optical efficiency no less than 90 %, focal length of about 3 cm and less, light spot of 2×2mm2, utilization of the total solar cell area, uniform light intensity distribution over the converter, manufacturing of a lens array and reflectors as monolithic structures saving time and cost, etc. These and other advantages allow one to expect a decrease in cost/W. For commercialization of the innovation it is necessary to develop and characterize a prototype of a CPV module using state-of-the-art high technologies compatible with commercial production.

An attempt is made to analyze and summarize the literature data on hybrid x-ray GaAs pixel detectors designed for medical imaging. Criteria are stated for selecting a semiconductor material. It is shown that GaAs is currently preferable to the other semiconductor materials. Detector figures of merit used to select a semiconductor material and a process technology are listed. Major types of x-ray detector based on bulk-grown or epitaxial GaAs are described, namely, the planar Schottky, the planar p-i-n, and the 3D detector. The influence is considered of different process steps (contact formation, passivation coating, hybridization, etc.) on detector figures of merit. Monolithic technology is briefly discussed.

The optical and electrical characteristics of p–n photodiodes based on monocrystalline n-Si (wafers with ρ = 70 and 10 Ohm · cm and SOI) implanted with B+ in the dose range of 1 × 1014–1 × 1015 сm−2 and annealed at 900 °C (20 min) are studied. The p–n structures exhibit photosensitivity in the short-wavelength infrared region (SWIR) with different maximum intensities depending on dose and n-Si resistivity. Leakage currents are also dose-dependent. The character of the SOI spectra is somewhat different. The optical and electrical properties of p–n photodiodes are described in terms of formation of extended defects with deep levels in the bandgap appearing after B implantation and annealing of n-Si. The importance of the damaged surface layer in the starting material for the observed effects is confirmed experimentally. The relation of the SWIR photoresponse intensity to the content of C and O gettered to the p–n structure surface is revealed. The innovative aspects of technology application are discussed.

A tremendous development in the field of imaging radiation detectors has taken place in the last decade. Conventional X-ray film has been replaced by digital X-ray imaging systems in a number of ways. Such systems mainly consist of silicon charge coupled devices (CCDs) where incident photons create electron-hole pairs in the thin silicon absorption layer near the surface. In contrast to visible light, which is absorbed within a 2 µm layer of silicon, the penetration of X-ray is much deeper due to higher photon energy. This disadvantage is often circumvented by the use of a scintillator absorption layer. Due to scattering of the low energy fluorescence photons, resolution and contrast of the X-ray images decrease. In order to eliminate these disadvantages, hybrid detectors consisting of direct converting semiconductors and readout electronics parts are fabricated. For this configuration, it is advantageous that both parts can be optimized separately and different materials can be used. Because of the well developed technology, the readout chip is fabricated out of silicon. As absorbing material, silicon is less suitable. In a silicon substrate of 500 µm thickness, only 15% of a 30 keV radiation is absorbed and converted into charges. In order to increase the absorption, materials with a higher atomic mass have to be used. Several compound semiconductors can be used for this purpose. One of them is GaAs, which is available as high quality semi-insulating wafer material. For detector optimization, GaAs wafers from several manufacturers with different properties were investigated. Test structures with Schottky and PIN diodes were fabricated. The I/V curves of the diodes, the spectral response from 5 up to 150 keV, the carrier concentration, and the carrier mobility were measured and compared. A survey of the results and the criteria for material selection resulting from these measurements will be provided in the paper.

For the last decade a tremendous development in the field of imaging radiation detectors has taken place. Conventional X-ray film has been replaced by digital X-ray imaging systems in a number of ways. Such systems mainly consist of silicon charge coupled devices (CCDs) where incident photons create electron-hole pairs in the thin silicon absorption layer near the surface. In contrast to visible light, which is absorbed within a 2 μm layer of silicon, the penetration of X-ray is much deeper due to higher photon energy. This disadvantage is often circumvented by the use of a scintillator absorption layer. Due to scattering of the low energy fluorescence photons, resolution and contrast of the X-ray images decrease. In order to eliminate these disadvantages, hybrid detectors consisting of direct converting semiconductors and readout electronics parts are fabricated. For this configuration, it is advantageous that both parts can be optimized separately and different materials can be used. Because of the well developed technology, the readout chip is fabricated out of silicon. As absorbing material, silicon is less suitable. In a silicon substrate of 500 μm thickness, only 15% of a 30 keV radiation is absorbed and converted into charges. In order to increase the absorption, materials with a higher atomic mass have to be used. Several compound semiconductors can be used for this purpose. One of them is GaAs, which is available as high quality semiinsulating wafer material. For detector optimization, GaAs wafers from several manufacturers with different properties were investigated. Test structures with Schottky and PIN diodes were fabricated. The I/V curves of the diodes, the spectral response from 5 up to 150 keV, the carrier concentration, and the carrier mobility were measured and compared. A survey of the results and the criteria for material selection resulting from these measurements will be provided in the paper.

Possibilities of gallium arsenide technology in Georgia to fabricate microelectronic devices are described. Characteristics of technological processes and parameters of active and passive components for digital and analog IC's are given. A concept of technology implementation with allowance for design, epistructure growth and processing is proposed which is the basis of a foundry service for application-specific microelectronic components.

To develop reliable intercomponent insulation methods to fabricate devices and IC's based on GaAs multiplayer heterostructures the formation of high-resistivity regions in these structures by selective F+ and B+ ion implantation is studied. The implantation and the consequent annealing regimes are established.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Molecular-beam - grown epitaxy heterostructure field-effect transistors employing a delta-doped channel have been fabricated and investigated. The results of studies of DC parameters of δ-FET's of different configuration can be regarded as the best obtained by other authors for single δ-doped structures. These data as well as the results of modeling and simulation allow one to recommend the studied δ-FET's for digital and analog applications.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper presents highlights and major achievements in research and development of GaAs technology in Georgia in three main directions: MESFETs, HEMTs and digital ICs; low-temperature stimulated processes; monolithic LED arrays for OEICs. The potential roadmaps of these technologies are also discussed.

The design technique of digital integrated circuits on BFL gates is represented on the basis of an AlGaAs/GaAs heterostructure. The high electron mobility transistor (HEMT) is simulated and the basic architecture and electrophysical parameters of the heterostructure are defined. Experimental samples of the HEMT (with gate length 0.8 /spl mu/m) on AlGaAs/GaAs heterostructures, manufactured by MBE, are in good agreement with the simulated transistor and the discrepancy does not exceed 10%.