Projection of two biphoton qutrits onto a maximally entangled state

Bell state measurements, in which two quantum bits are projected onto a maximally entangled state, are an essential component of quantum information science. We propose and experimentally demonstrate the projection of two quantum systems with three states (qutrits) onto a generalized maximally entangled state. Each qutrit is represented by the polarization of a pair of indistinguishable photons - a biphoton. The projection is a joint measurement on both biphotons using standard linear optics elements. This demonstration enables the realization of quantum information protocols with qutrits, such as teleportation and entanglement swapping.Comment: 4 pages, 3 figures, published versio

The influence of defoliation and nitrogen on the regrowth of Rhodes grass (Chloris gayana Kunth). 2. Etiolated growth and non-structural carbohydrate, total-N and nitrate-N content.

Data are given on the chemical composition of Rhodes grass cv. Common grown in a heated glasshouse [see HbA 42, 1910]. Plants given high N (8.29 meq/100 g soil) contained about 30% less carbohydrate in the stubble and roots than those given low N (1.43 meq/100g). The carbohydrate content of plants cut every 28 days was generally lower than that of plants cut every 14 days. Amounts of etiolated growth in darkness after cutting were positively correlated with the carbohydrate level in the roots and in the stubble. The percentage of tillers exhibiting regrowth in darkness increased linearly up to about 60% with increase in the amount of etiolated growth. Contents of total N in roots and in stubble were almost double at the high rate of N. Amounts of nitrate as a proportion of total N were about 12% in low-N plants and up to 47% in high-N plants. The nitrate contents of shoots, stubble and roots were negatively correlated with the carbohydrate levels in each of these tissues. The overall difference in carbohydrate level between shoots, stubble and roots was relatively small. It was concluded that Rhodes grass had a limited capacity to accumulate reserve material when grown under conditions favouring rapid growth. (Abstract retrieved from CAB Abstracts by CABI’s permission

The influence of defoliation and nitrogen on the regrowth of Rhodes grass (Chloris gayana Kunth). 1. Dry matter production and tillering.

In pot experiments Rhodes grass (cv. "Common" and "Katambora") was fertilized with 1.43 and 8.29 meq N/100 g soil over a period of 56 days and was cut every 14 or 28 days. Cutting at 28 days considerably increased total shoot weight. Root weight per pot of low-N plants was 31 and 23% higher than that of high-N plants at 14- and 28-day cutting intervals, respectively. N application generally increased the average number of harvest tillers, but individual tillers regrew a fewer number of times than those receiving low N. (Abstract retrieved from CAB Abstracts by CABI’s permission

Regrowth potential of shoot and of roots of Rhodes grass (Chloris gayana Kunth) after defoliation.

In field and pot trials the effect of different lengths of pre-cutting periods and of cutting intervals on regrowth of shoot and of root were studied in Rhodes grass cv. Katambora. The initial regrowth of the sward after a long (28 days) pre-cutting period was slower than after a short (7 days) pre-cutting period. The reduction of the residual LAI following the extension of the pre-cutting period was associated with reduction in the number of tillers capable of regrowth after defoliation. Root wt. decreased drastically following cutting when the initial root wt. was high (long pre-cutting period), but little when the initial root wt. was small (short pre-cutting period). The decrease in root wt. lasted c. 1 wk after which it increased at a more or less constant rate proportional to the increase of shoot wt. irrespective of the length of the pre-cutting period. The lack of the capability of tillers to regrow after cutting was closely related with developmental stage of tillers. Since tillers of subtropical and tropical grasses have a tendency for early stem elongation, it was concluded that the relatively small number of sites available for regrowth in these grasses is the major deterrent for quick shoot growth of the sward after defoliation. (Abstract retrieved from CAB Abstracts by CABI’s permission

Effects of electromagnetic radiation on intact bovine lens epithelium in culture conditions

Цель: исследовать влияние неионзирующего электромагнитного излучения на хрусталик глаза, с использованием культуры ткани хрусталика глаза. Методы: Хрусталики бычьего глаза были культивированы в течение 10 дней. Изучено 59 хрусталиков. Обработанные хрусталики были облучены 1.1 GHz, 2.22mW в течение 192 циклов по 50 минут с паузой 10 минут. Затем в контрольных и обработанных культуральных клетках хрусталика определяли активность ферментов. Результаты: Экспозиция 2.22mW и 1.1GHz повредила хрусталик глаза. Лучевое повреждение проявилось в эпителиальном слое хрусталика глаза, и сопровождалось изменениями активности эпителиальных ферментов. Выводы: Электромагнитное излучение имеет выраженное воздействие на хрусталик глаза Экспозиция описанными выше уровнями удельной энергии воздействует на эпителий хрусталика глаза, что выражается в изменении активности эпителиальных ферментов.Purpose: To investigate the effects of nonionizing electromagnetic radiation on the eye lens using a lens organ culture system. Methods: Bovine lenses were incubated in organ culture conditions for 10 days. 59 lenses were used in this study. Treated lenses were exposed to 1.1GHz, 2.22mW for 192 cycles of 50 minutes irradiation followed by 10 minutes pause. At the end of the culture period control and treated lenses were taken for enzyme analysis. Results: Exposure to 2.22mW at 1.1GHz caused damage to the lens. The radiation damage appeared at the lens epithelial layer accompanied by activity changes of lens epithelial enzymes. Conclusions: Electromagnetic radiation has a clear impact on the eye lens. Exposure above specific energy levels affects lens epithelium as demonstrated by changes in epithelial enzyme activities

Protection of a lens of an eye against the simulated diabetic cataract

Катаракта является очень распространенным осложнением при диабете. Мы подвергли бычие линзы действию высокой концентрации глюкозы (450 мг.%) в условиях культуры в течение двух недель и исследовали повреждения в линзе и возможную защиту специальными антиоксидантами N ацетил L цистеином (NAC) и цинковым комплексом desferrioxamine (DFO), селективным хелатором для железа. Исследовалось оптическое качество линз и окисление эпителия с дихлорфлюоресцеином (DCF), а также оценивались изменения в 2D гель электрофоретическом профиле белков хрусталика. Наблюдались изменения при высоком содержании глюкозы в фокусном расстоянии линзы, повышении окисления. NAC И Zn DFO почти полностью защищали линзы; DFO показывал только частичную защиту. Результаты демонстрировали, что антиоксиданты могут защищають хрусталик повреждающего действия высоких концентраций глюкозы. Комбинация NAC и ZnDFO действовала более эффективно.Катаракта є дуже поширеним ускладненням при діабеті. Ми піддали кришталик ока бика дії високої концентрації глюкози (450 мг %) в умовах культури протягом двох тижнів і досліджували пошкодження в лінзі і можливий захист спеціальними антиоксидантами N ацетил L цистеином (NAC) і цинковим комплексом desferrioxamine (DFO), селективним хелатором для заліза. Досліджувалася оптична якість лінз і окислення епітелію з дихлорфлюоресцеїном (DCF), а також оцінювалися зміни в 2D гель електрофоретичному профілі білків кришталика. Спостерігалися зміни при високому вмісті глюкози у фокусній відстані лінзи, підвищенні окислення. NAC І Zn DFO майже повністю захищали лінзи; DFO показував тільки частковий захист. Результати демонстрували, що антиоксиданти можуть защищають кришталик від ушкоджувальної дії високих концентрацій глюкози. Комбінація NAC і ZNDFO діяла ефективніше

The biaxial nonlinear crystal BiB3O6 as a polarization entangled photon source using non-collinear type-II parametric down-conversion

We describe the full characterization of the biaxial nonlinear crystal BiB3O6 (BiBO) as a polarization entangled photon source using non-collinear type-II parametric down-conversion. We consider the relevant parameters for crystal design, such as cutting angles, polarization of the photons, effective nonlinearity, spatial and temporal walk-offs, crystal thickness and the effect of the pump laser bandwidth. Experimental results showing entanglement generation with high rates and a comparison to the well investigated beta-BaB2O4 (BBO) crystal are presented as well. Changing the down-conversion crystal of a polarization entangled photon source from BBO to BiBO enhances the generation rate as if the pump power was increased by more than three times. Such an improvement is currently required for the generation of multiphoton entangled states.Comment: 15 pages, 13 figures, published versio

High oxygen load causes damage to lens epithelium which is reduced by antioxidants

Цель: Изучить механизмы воздействия кислорода на хрусталик и возможный защитный эффект цинк-дезферриоксамина (Zn-DFO). Методы: Хрусталики, полученные из глаза быка, хранили на культуре, полученной из тканей данного органа. Хрусталик подвергали воздействию значительной кислородной нагрузки либо в присутствии, либо без комплекса Zn-DFO (20 ЦІМ). Оптические свойства хрусталика оценивали через семь дней от начала выращивания культуры. По завершении периода, хрусталик извлекали и проводили его морфологический и ферментный анализ. Результаты: В хрусталиках, подвергнутых воздействию больших концентраций кислорода, наблюдали уменьшение оптических свойств и изменение активности энзимов эпителия изучаемого органа. При анализе активности энзимов изучали цикл Кребса, течение гликолиза и состояние АТФ пограничных мембран. Добавление Zn-DFO к культуре клеток до начала воздействия кислородом, элиминировало большую часть кислородозависимых повреждений. Выводы: Полученные результаты могут указывать на возможную роль Zn-DFO как защитного агента при возникновении кислород-индуцированных катаракт.Purpose: To investigate the mechanisms involved in the effects of oxygen on the eye lens and the possible protective effects of Zinc-desferrioxamine (Zn-DFO) using lens organ culture system. Methods: Bovine lenses, kept in an organ culture system, were exposed to high oxygen load in the presence or absence of Zn-DFO complex (20 MM). Lens optical quality was assessed throughout the 7 days of the culture period. At the end of the culture, lenses were taken for morphological and enzyme analysis. Results: Decreased lenticular optical quality and changes in lens epithelium enzymatic activities were observed in lenses exposed to high oxygen concentration. The enzymes analyzed were from Krebs cycle, glycolysis pathway and membrane bound ATPase. Addition of Zn-DFO to the culture before the exposure to oxygen eliminated most of the oxygen-induced damage. 126) Conclusions: The present results may indicate a possible role of Zn-DFO as a protective agent against oxygen-induced cataract formation