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The Moscow Institute for Nuclear Research atomic‐beam type source of polarized negative hydrogen ions is described. The production of H− ions is based on the resonant charge exchange of polarized thermal hydrogen atoms and D− ions in deuterium plasma. Improvements in the D− plasma source are outlined. The polarized source produces a pulsed H− beam with a peak current up to 1 mA and a pulse duration of 180 μs at a repetition rate of 10 Hz. The normalized emittance for 90% of the beam particles is 1.8 π mm mrad. The polarimeter of low energy H− ions is also described. The polarization of the H− ions was measured to be 0.87±0.02.

Polarized negative hydrogen ion beam with peak current of 2.5 mA has been obtained from an atomic beam-type polarized ion source of Institute for Nuclear Research, Moscow. The intensity improvement has been achieved due to increase of efficiency of conversion of polarized hydrogen atoms into polarized negative ions. New converter for production of deuterium plasma with high density of unpolarized negative ions is described. Limitations of the method and possible improvements are discussed.

A test of a storage cell in the ionizer of the atomic beam-type polarized ion source is described. The cylindrical aluminum storage cell with uncoated walls and with internal diameter 1.5 cm had been placed in the charge-exchange region of the plasma ionizer. A pulsed polarized hydrogen atomic beam was injected into the storage cell from one side, and deuterium plasma was injected from the other side through an orifice with a diameter of 3 mm. The tests were made with a pulsed deutron ion beam of 5 mA. Results of intensity and polarization measurements for the polarized proton beam extracted are presented. The intensity gain obtained with the storage cell in comparison with operation without the storage cell was measured to be 9.0. The polarization of the proton beam from the storage cell reaches 0.94±0.03. Possible schemes for production of polarized negative hydrogen ions and polarized 3He++ ions with a storage cell are discussed.

The Moscow INR atomic‐beam type source of polarized negative hydrogen ions is described. The production of H− ions is based on resonant charge exchange between polarized thermal hydrogen atoms and D− ions in a deuterium plasma. Improvements in the D− plasma source are outlined. The polarized source produces a pulsed H− beam with the peak current up to 1 mA and pulse duration of 180 μs at repetition rate 10 Hz. The normalized emittance for 90% of the beam particles is 1.8 π mm mrad. The polarization of low energy H− ions was measured to be 0.87±0.02.

Introduction 614 I. Physical principles of experiments in colliding beams 614 II. Principal storage ring constructions 617 III. Processes occurring upon storage of electrons and positrons 621 IV. Structural features of storage rings 627 Cited references 637

Aim: Oxidative stress plays a role in the pathogenesis of radiation induced male infertility. Ellagic acid; is a polyphenolic compound with antioxidant properties. The aim of the study is to investigate the effect of allygic acid on testicular tissue in exposed rats. Material-Method: In the study, 30 male Spraque-Dawley rats were used for 8 weeks. The rats were divided into five groups n: 6 : group I control , group II radiation , group III radiation + ellagic acid , group IV ellagic acid , group V corn oil . The rats in radiation group and radiation + ellajic acid group were exposed to a single dose of 8 Gy of radiation on the first day of study. The rats in radiation + ellajic acid group and ellajic acid group were given 12 mg / kg ellagic acid dissolved in corn oil for 7 weeks by oral gavage from the second day of study. At the end of the experiment period, all rats were decapitated. Testicular tissue removed. TUNEL method was applied with histochemical staining. Biochemical analyzes were performed. Results: In the histological evaluations, degeneration of seminiferous tubular germinal epithelium, vascular congestion, atrophic tubules, interstitial area, edema and immature cells spilled in the lumens of some tubules were detected in sections of radiation group. Significant improvements were observed in radiation + ellajic acid group compared to radiation group. When compared with control group, an increase in TUNEL positive cell number was detected in radiation group, but no increase in radiation + ellajic acid group was observed. Compared to control group, malondialdehyde MDA levels significantly increased, superoxide dismutase SOD activity decreased in radiation group; whereas in radiation + ellajic acid group, MDA level decreased and SOD activity increased. Conclusion: It has been determined that the radiation dose at the indicated dose damages the testicular tissue. Ellajic acid application; it has been observed that the antioxidant property significantly reduces the adverse effects of radiation, Amaç: Radyasyon nedenli erkek infertilitesinin patogenezinde oksidatif stres rol oynar. Ellajik asit; antioksidan özelliğe sahip polifenolik bir bileşiktir. Çalışmada radyasyona maruz kalan ratlarda ellajik asidin testis dokusundaki etkisinin incelenmesi amaçlanmaktadır. Gereç-Yöntem: Çalışmada 8 haftalık 30 adet Spraque-Dawley cinsi erkek rat kullanıldı. Ratlar beş gruba ayrıldı n:6 : grup I kontrol , grup II radyasyon , grup III radyasyon+ellajik asit , grup IV ellajik asit , grup V mısırözü yağı . Radyasyon ve radyasyon+ellajik asit gruplarındaki ratlar, çalışmanın ilk gününde, tek doz 8 Gy’lik radyasyona maruz bırakıldılar. Radyasyon+ellajik asit ve ellajik asit gruplarındaki ratlara çalışmanın ikinci gününden itibaren 7 hafta boyunca mısırözü yağında çözdürülmüş 12 mg/kg dozunda ellajik asit gün aşırı oral gavajla verildi. Deney süresi sonunda tüm ratlar dekapite edildi. Testis dokuları çıkarıldı. Histokimyasal boyamalar ile TUNEL yöntemi uygulandı. Biyokimyasal analizler yapıldı. Bulgular: Histolojik değerlendirmelerde radyasyon grubuna ait kesitlerde seminifer tübül germinal epitelinde dejenerasyon, vasküler konjesyon, atrofik tübüller, interstisyel alanda ödem ve bazı tübüllerin lümenlerine dökülmüş immatür hücreler tespit edildi. Radyasyon+ellajik asit grubuna ait kesitler, radyasyon grubu ile karşılaştırıldığında ise belirgin iyileşmeler gözlendi. Kontrol grubu ile karşılaştırıldığında radyasyon grubunda TUNEL pozitif hücre sayısında artış tespit edilirken, radyasyon+ellajik asit grubunda herhangi bir artış izlenmedi. Kontrol grubu ile kıyaslandığında radyasyon grubunda malondialdehit MDA düzeylerinin anlamlı düzeyde arttığı, süperoksit dismutaz SOD aktivitesinin ise azaldığı; radyasyon+ellajik asit grubunda ise MDA seviyesinin azaldığı, SOD aktivitesinin ise arttığı tespit edildi. Sonuç: Belirtilen dozda radyasyon uygulamasının testis dokusuna hasar verdiği tespit edildi. Ellajik asit uygulamasının ise; antioksidan özelliği sayesinde radyasyonun oluşturduğu olumsuz etkileri belirgin biçimde azalttığı gözlendi