Cyclotron-resonant exciton transfer between the nearly free and strongly localized radiative states of a two-dimensional hole gas in a high magnetic field

Avoided crossing of the emission lines of a nearly free positive trion and a cyclotron replica of an exciton bound to an interface acceptor has been observed in the magneto-photoluminescence spectra of p-doped GaAs quantum wells. Identification of the localized state depended on the precise mapping of the anti-crossing pattern. The underlying coupling is caused by an exciton transfer combined with a resonant cyclotron excitation of an additional hole. The emission spectrum of the resulting magnetically tunable coherent state probes weak localization in the quantum well.Comment: 5 pages, 5 figure

Optical manipulation of the exciton charge state in single layer tungsten disulfide

Raman scattering and photoluminescence (PL) emission are used to investigate a single layer of tungsten disulfide (WS$_{2}$) obtained by exfoliating n-type bulk crystals. Direct gap emission with both neutral and charged exciton recombination is observed in the low temperature PL spectra. The ratio between the trion and exciton emission can be tuned simply by varying the excitation power. Moreover, the intensity of the trion emission can be independently tuned using additional sub band gap laser excitation

Unintentional high density p-type modulation doping of a GaAs/AlAs core-multi-shell nanowire

Achieving significant doping in GaAs/AlAs core/shell nanowires (NWs) is of considerable technological importance but remains a challenge due to the amphoteric behavior of the dopant atoms. Here we show that placing a narrow GaAs quantum well in the AlAs shell effectively getters residual carbon acceptors leading to an \emph{unintentional} p-type doping. Magneto-optical studies of such a GaAs/AlAs core multi-shell NW reveal quantum confined emission. Theoretical calculations of NW electronic structure confirm quantum confinement of carriers at the core/shell interface due to the presence of ionized carbon acceptors in the 1~nm GaAs layer in the shell. Micro-photoluminescence in high magnetic field shows a clear signature of avoided crossings of the $n=0$ Landau level emission line with the $n=2$ Landau level TO phonon replica. The coupling is caused by the resonant hole-phonon interaction, which points to a large 2D hole density in the structure.Comment: just published in Nano Letters (http://pubs.acs.org/doi/full/10.1021/nl500818k

Mutation increasing β-carotene concentrations does not adversely affect concentrations of essential mineral elements in pepper fruit

<div><p>Vitamin and mineral deficiencies are prevalent in human populations throughout the world. Vitamin A deficiency affects hundreds of millions of pre-school age children in low income countries. Fruits of pepper (<i>Capsicum annuum</i> L.) can be a major dietary source of precursors to Vitamin A biosynthesis, such as β-carotene. Recently, pepper breeding programs have introduced the orange-fruited (<i>of</i>) trait of the mutant variety Oranzheva kapiya, which is associated with high fruit β-carotene concentrations, to the mutant variety Albena. In this manuscript, concentrations of β-carotene and mineral elements (magnesium, phosphorus, sulphur, potassium, zinc, calcium, manganese, iron and copper) were compared in fruit from P31, a red-fruited genotype derived from the variety Albena, and M38, a genotype developed by transferring the orange-fruited mutation (<i>of</i>) into Albena. It was observed that fruit from M38 plants had greater β-carotene concentration at both commercial and botanical maturity (4.9 and 52.7 mg / kg fresh weight, respectively) than fruit from P31 plants (2.3 and 30.1 mg / kg fresh weight, respectively). The mutation producing high β-carotene concentrations in pepper fruits had no detrimental effect on the concentrations of mineral elements required for human nutrition.</p></div

Clinical Screening Tools for Sarcopenia and Its Management

Sarcopenia, an age-related decline in muscle mass and function, is affecting the older population worldwide. Sarcopenia is associated with poor health outcomes, such as falls, disability, loss of independence, and mortality; however it is potentially treatable if recognized and intervened early. Over the last two decades, there has been significant expansion of research in this area. Currently there is international recognition of a need to identify the condition early for intervention and prevention of the disastrous consequences of sarcopenia if left untreated. There are currently various screening tools proposed. As yet, there is no consensus on the best tool. Effective interventions of sarcopenia include physical exercise and nutrition supplementation. This review paper examined the screening tools and interventions for sarcopenia

Sensorineural hearing loss in Lassa fever: two case reports

<p>Abstract</p> <p>Introduction</p> <p>Lassa fever is an acute arena viral haemorrhagic fever with varied neurological sequelae. Sensorineural hearing loss is one of the rare complications which occur usually during the convalescent stage of the infection.</p> <p>Case presentation</p> <p>The cases of two female patients aged 19 and 43 years old, respectively, with clinical features suggestive of Lassa fever and confirmed by immunoserological/Lassa-virus-specific reverse transcriptase polymerase chain reaction are presented. Both patients developed severe sensorineural hearing loss at acute phases of the infections.</p> <p>Conclusion</p> <p>Sensorineural hearing loss from Lassa fever infections can occur in both acute and convalescent stages and is probably induced by an immune response.</p

Using Swallowing Quality of Life to Compare Oropharyngeal Dysphagia Following Cervical Disc Arthroplasty or Anterior Cervical Discectomy and Fusion

Objective To evaluate dysphagia outcomes using the swallowing quality of life (SWAL-QOL) questionnaire between patients undergoing cervical disk arthroplasty (CDA) or anterior cervical discectomy and fusion (ACDF). Methods Patient-reported outcome measures (PROMs) were collected using SWAL-QOL, VAS, NDI, and SF-12 PCS. All measures were recorded preoperatively to 6-month postoperatively. Patients were grouped according to cervical procedure and instrumentation used. Differences in PROMs and SWAL-QOL domains were evaluated by t-test and one-way ANOVA with post-hoc testing, respectively. Simple linear regression was employed to evaluate the relationship between number of levels operated on and postoperative outcomes. Results 161 patients were included. CDA patients had significantly worse SWAL-QOL scores at 6-months. Preoperative VAS neck was significantly worse for patients who underwent either an ACDF procedure with a stand-alone cage or CDA as compared to patients who underwent an ACDF with anterior plating. At 6-months postoperatively, CDA patients reported a significantly worse “fatigue” score compared to ACDF patients. At 6-months postoperatively, ACDF patients reported a significantly better “sleep” scores compared to CDA patients with both recipients of an anterior plate and stand-alone cage reporting significantly better scores compared to the CDA cohort (p=0.024; p<0.001). The SWAL-QOL domain of symptom frequency at 6-weeks postoperatively was significantly associated with number of levels operated (p=0.032). Conclusion Patients undergoing either an ACDF or CDA procedure largely did not demonstrate differences in pain, disability, and dysphagia scores. However, at more longitudinal timepoints CDA patients reported worse fatigue and sleep scores compared to ACDF patients

Wplyw terminu siewu nasion na wielkosc i jakosc plonu bylicy estragonu [Artemisia dracunculus L.] uprawianej na zbior peczkowy

The aim of the study was to estimate the influence of a sowing date (10 April, 25 April and 10 May) on the quantity and quality of the yield of tarragon grown for a bunch harvest. The yields of tarragon plants were assayed in 2004-2006. Chemical analyses were made in the years 2004 and 2005. In the dry plant material, the content of macro- and microelements: total nitrogen, phosphorus, potassium, calcium, sodium, magnesium, manganese, zinc, iron and copper was assessed. Moreover, the content of essential oils in dry plant material was estimated. In the raw plant material, the content of L-ascorbic acid and the scavenging effect on DPPH radical were measured. It was proved that the sowing dates had a significant effect on the yield quantity. Significantly higher yield (424.5 kg⋅100 m-2) was obtained when seeds were sown on 10 May. The yield significantly decreased when seeds were sown on 10 April. The test sowing dates had no significant effect on the biometrical characteristics of tarragon plants during the harvest; only the leaves were significantly wider when the earliest sowing date was used. The yields were characterized by a high content of mineral compounds. However, the content of iron was twice as high in 2004 as in 2005. Also, the content of zinc and copper was higher in the first year of the study, respectively by 87.2% and 76.9%, compared with the yield obtained in the year 2005. The content of essential oils (mean for years of the study) was 0.59%, that of L-ascorbic acid was 10.08 mg⋅100 g-1 f.m. and the scavenging effect of tarragon herb on DPPHradical was 26.74%.W latach 2004–2006 badano wpływ terminu siewu nasion (10 i 25 kwietnia oraz 10 maja) na wielkość i jakość plonu bylicy estragonu, uprawianej na zbiór pęczkowy. W części laboratoryjnej badań (2004 i 2005), w próbie zbiorczej – ze wszystkich zbiorów i terminów uprawy – oceniono zawartość makro- i mikroskładników: azotu ogólnego, fosforu, potasu, wapnia, magnezu i sodu oraz cynku, manganu, żelaza i miedzi. Zawartość olejku eterycznego oznaczono w powietrznie suchym zielu metodą destylacji próbki surowca z wodą. W świeżej masie ziela wykonano oznaczenie zawartości kwasu L-askorbinowego oraz aktywność zmiatania rodników DPPH. Wykazano, iż badane terminy siewu wpłynęły istotnie na wielkość plonu ziela estragonu. Istotnie największy plon (424,5 kg⋅100 m-2) otrzymano z wysiewu w najpóźniejszym terminie (10 maja). Plon ten istotnie zmniejszał się wraz z przyspieszaniem terminu siewu, tj. do ok. 10 kwietnia. Terminy siewu nie miały istotnego wpływu na parametry biometryczne roślin w czasie ich zbioru, jedynie szerokość liści była istotnie większa w przypadku najwcześniejszego terminu uprawy. W uzyskanym plonie estragonu stwierdzono wysoką zawartość składników mineralnych, zbliżoną w poszczególnych latach badań. Największe różnice wystąpiły w zawartości żelaza, którego w roślinach w 2004 r. było ponad dwukrotnie więcej niż w kolejnym roku badań. Również w tym roku odnotowano w estragonie znacznie wyższą zawartość cynku (o 87,2%) i miedzi (o 76,9%) w porównaniu z zebranym w 2005 roku. Zawartość olejku eterycznego (średnio w latach badań) wyniosła 0,59%, kwasu L-askorbinowego 10,08 mg⋅100 g-1 ś.m.), a zdolność redukcji rodników DPPH kształtowała się na poziomie 26,74%

Zawartosc wybranych mikroelementow w swiezych nasionach bobu

W pracy określono zawartość suchej masy, popiołu oraz wybranych mikroelementów (Mn, Cu, Zn i Fe) w świeżych nasionach trzech drobnonasiennych odmian bobu - Orlik, Jupiter i Nowo oraz trzech odmian wielkonasiennych - Bachus, Basta i Windsor Biały. Wykazano, że nasiona bobu stanowią bogate źródło mikroelementów, a zwłaszcza żelaza i cynku. Wszystkie badane w doświadczeniu odmiany drobnonasienne bobu charakteryzowały się istotnie większą zawartością cynku, w porównaniu z odmianami wielkonasiennymi. Za wyjątkiem odmiany Nowo, cechowała je także wysoka zawartość suchej masy i popiołu w przeliczeniu na świeżą masę. Jako bogate źródło mikropierwiastków, spośród badanych w doświadczeniu odmian drobnonasiennych bobu, uznano dwie: Orlik i Jupiter.The content of dry matter, ash and some microelements in fresh seeds of three small seed cultivars of broad bean (Orlik, Jupiter and Nowo) and three large seed cultivars (Bachus, Basta and Windsor Biały) were investigated. It was proved that broad bean seeds constitute a rich source of microelements, especially of iron and zinc. All of the small seed cultivars were characterized by significantly higher content of zinc in comparison with large seed cultivars. Moreover, they contained higher amounts of dry matter and ash (to the fresh matter basis), just with one exception of Nowo cv. From among the small seed cultivars as a best source of microelements Orlik and Jupiter cvs. were found

Cechy jakosciowe oraz zawartosc skladnikow mineralnych w owocach wybranych odmian papryki [Capsicum annuum L.]

The study was carried out in 2005–2007. The aim of the experiment was to estimate the quality and mineral compound content in sweet pepper fruits. The experimental material consisted of seven F1 hybrids grown in the open field: ISI 56511 F1, ISI 56503 F1, Axel F1, Akron F1, Roei F1, Elfo F1 and Polonez F1 (control cultivar). The fruits were harvested many times. They were collected when green and fully grown. After the harvest, the fruit quality including its mean weight, length, diameter, pericarp weight and pericarp thickness, was evaluated. In 2006-2007, the content of macro– and microelements, such as nitrogen, phosphorus, potassium, sodium, calcium, magnesium, iron, zinc and nitrates was determined in the dry weight of the yield. The results were statistically evaluated by the analysis of variance. Significance of the differences was tested by Tukey’s test at p = 0.05. The biometrical traits of fruits were characteristic for each cultivar. The highest content of dry weight was found for cultivar ISI 56511 F1 (11.2% higher than the mean amount determined for all of the cultivars and 39.8% higher than the lowest dry matter content assessed in fruits of cultivar Roei F1). The sweet pepper cultivars tested in the experiment differed significantly in the content of macro- and microelements. The highest content of nitrogen was determined in fruits of cultivar Polonez F1. Fruits produced by cultivars Elfo F1, ISI 56503 F1 and Roei F1 in comparison with the other cultivars were characterized by a significantly higher content of iron. The highest content of nitrates was assessed in cultivar ISI 56503 F1 fruit.W latach 2005–2007 badano jakość owoców papryki i zawartość makro- i mikroskładników. Badaniom (uprawa polowa) poddano następujące odmiany papryki: ISI 56511 F1, ISI 56503 F1, Axel F1, Akron F1, Roei F1, Elfo F1 i Polonez F1 (odmiana kontrolna). Zbiór owoców papryki wykonywano wielokrotnie, zbierano owoce zielone w pełni wyrośnięte. Po zbiorach owoce poddano ocenie jakościowej, uwzględniając ich masę, długość, średnicę oraz masę i grubość perykarpu. W latach 2006-2007 w suchej masie plonu oznaczono zawartość: makro– i mikroskładników – azotu ogólnego, fosforu, potasu, sodu, wapnia, magnezu, żelaza, cynku oraz azotanów. Wyniki opracowano statystycznie testem Tuckeya, wyliczając półprzedziały ufności na poziomie istotności α = 0,05. Badane cechy biometryczne owoców były charakterystyczne dla poszczególnych odmian papryki. Istotnie najwięcej suchej masy zawierały owoce odmiany ISI 56511 F1 – o 11,2% więcej od średniej zawartości w owocach wszystkich badanych odmian i o 39,8% więcej w porównaniu z najmniejszą jej zawartością, oznaczoną w owocach odmiany Roei F1. Badane odmiany papryki różniły się istotnie zawartością makro– i mikroskładników. Najwięcej azotu ogólnego i potasu zawierały owoce odmiany Polonez F1. W owocach odmian Elfo F1, ISI 56503 F1 i Roei F1 oznaczono – w porównaniu z pozostałymi badanymi odmianami – istotnie większą zawartość żelaza. Istotnie najwięcej azotanów zawierały owoce odmiany ISI 56503 F1