1,334 research outputs found

    Comment on "Band structure engineering of graphene by strain: First-principles calculations"

    Full text link
    In their first-principles calculations of the electronic band structure of graphene under uniaxial strain, Gui, Li, and Zhong [Phys. Rev. B \textbf{78}, 075435 (2008)] have found opening of band gaps at the Fermi level. This finding is in conflict with the tight-binding description of graphene which is closed gap for small strains. In this Comment, we present first-principles calculations which refute the claim that strain opens band gaps in graphene.Comment: published versio

    Energy gap opening in submonolayer lithium on graphene: Local density functional and tight-binding calculations

    Full text link
    The adsorption of an alkali-metal submonolayer on graphene occupying every third hexagon of the honeycomb lattice in a commensurate (3×3)R30(\sqrt{3}\times\sqrt{3})R30^\circ arrangement induces an energy gap in the spectrum of graphene. To exemplify this type of band gap, we present \textit{ab initio} density functional theory calculations of the electronic band structure of C6_6Li. An examination of the lattice geometry of the compound system shows the possibility that the nearest-neighbor hopping amplitudes have alternating values constructed in a Kekul\'e-type structure. The band structure of the textured tight-binding model is calculated and shown to reproduce the expected band gap as well as other characteristic degeneracy removals in the spectrum of graphene induced by lithium adsorption. More generally we also deduce the possibility of energy gap opening in periodic metal on graphene compounds Cx_xM if xx is a multiple of 3.Comment: 7 pages, 5 figures, published versio

    The AT(N) framework for Alzheimer\u27s disease in adults with Down syndrome

    Get PDF
    The National Institute on Aging in conjunction with the Alzheimer\u27s Association (NIA-AA) recently proposed a biological framework for defining the Alzheimer\u27s disease (AD) continuum. This new framework is based upon the key AD biomarkers (amyloid, tau, neurodegeneration, AT[N]) instead of clinical symptoms and represents the latest understanding that the pathological processes underlying AD begin decades before the manifestation of symptoms. By using these same biomarkers, individuals with Down syndrome (DS), who are genetically predisposed to developing AD, can also be placed more precisely along the AD continuum. The A/T(N) framework is therefore thought to provide an objective manner by which to select and enrich samples for clinical trials. This new framework is highly flexible and allows the addition of newly confirmed AD biomarkers into the existing AT(N) groups. As biomarkers for other pathological processes are validated, they can also be added to the AT(N) classification scheme, which will allow for better characterization and staging of AD in DS. These biological classifications can then be merged with clinical staging for an examination of factors that impact the biological and clinical progression of the disease. Here, we leverage previously published guidelines for the AT(N) framework to generate such a plan for AD among adults with DS

    Synthetic Brassica napus L.: Development and Studies on Morphological Characters, Yield Attributes, and Yield

    Get PDF
    Brassica napus was synthesized by hybridization between its diploid progenitor species B. rapa and B. oleracea followed by chromosome doubling. Cross with B. rapa as a female parent was only successful. Among three colchicine treatments (0.10, 0.15, and 0.20%), 0.15% gave the highest success (86%) of chromosome doubling in the hybrids (AC; 2n = 19). Synthetic B. napus (AACC, 2n = 38) was identified with bigger petals, fertile pollens and seed setting. Synthetic B. napus had increased growth over parents and exhibited wider ranges with higher coefficients of variations than parents for morphological and yield contributing characters, and yield per plant. Siliqua length as well as beak length in synthetic B. napus was longer than those of the parents. Number of seeds per siliqua, 1000-seed weight and seed yield per plant in synthetic B. napus were higher than those of the parents. Although flowering time in synthetic B. napus was earlier than both parents, however the days to maturity was little higher over early maturing B. rapa parent. The synthesized B. napus has great potential to produce higher seed yield. Further screening and evaluation is needed for selection of desirable genotypes having improved yield contributing characters and higher seed yield

    Combining Ability Analysis in Complete Diallel Cross of Watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai)

    Get PDF
    The experiments were carried out in two research stations (MARDI Bukit Tangga, Kedah, and MARDI Seberang Perai, Penang) in Malaysia. The crossings were performed using the four inbred lines in complete diallel cross including selfs and reciprocals. We evaluated the yield components and fruit characters such as fruit yield per plant, vine length, days to fruit maturity, fruit weight, total soluble solid content, and rind thickness over a period of two planting seasons. General combining ability and its interaction with locations were statistically significant for all characteristics except number of fruits per plant across the environments. Results indicated that the additive genetic effects were important to the inheritance of these traits and the expression of additive genes was influenced greatly by environments. In addition, specific combining ability effect was statistically evident for fruit yield per plant, vine length, days to first female flower, and fruit weight. Most of the characters are simultaneously controlled by additive and nonadditive gene effects. This study demonstrated that the highest potential and promising among the crosses was cross P2 (BL-14) × P3 (6372-4), which possessed prolific plants, with early maturity, medium fruit weight and high soluble solid contents. Therefore this hybrid might be utilized for developing high yielding watermelon cultivars and may be recommended for commercial cultivation

    Rehabilitation in acute post COVID-19 symptoms with intracranial space occupying lesion: a case report

    Get PDF
    Coronavirus disease (COVID-19) is an infectious disease caused by the SARS-CoV-2. Older people and those with underlying medical conditions like cardiovascular disease, diabetes, chronic respiratory disease or cancer is more likely to develop serious illness. Acute post COVID-19 patients will get a variety of problems with normal functioning. Rehabilitation could be an effective method for decreasing COVID-19's effects on patient health and function. A 20 years old, female was diagnosed with COVID-19 5 weeks ago, it had been reported shortness of breath, difficult clearing phlegm, headache, nausea and vomiting. The patient had a history of intracranial space occupying lesion (SOL), cerebello pontine angle (CPA) tumor 3 years ago, craniotomy resection of 4th ventricular tumour one year ago and a second craniotomy scheduled for 2021. Several exercises were scheduled for patients including prone position, respiratory muscle training, controlled breathing techniques, bronchial hygiene-airway clearance techniques, aerobic exercise, three times a week, exercises were scheduled. After having completed the exercise program for four weeks, exercise improved shortness of breath, phlegm expenditure, muscle strength, improve lung recoil, vital capacity, range of motion, patient balance and the patient's ability to maximize activity

    Dampak Hukum Peceraian Akibat Kekerasan Dalam Rumah Tangga (Studi Kasus di Pengadilan Agama Kelas 1A Makassar Tahun 2013-2015)

    Get PDF
    Hasil penelitian ini menunjukan bahwa: 1.) Faktor yang menyebabkan terjadinya perceraian yang disebabkan oleh kekerasan dalam rumah tangga adalah antara lain: a.) Rendahnya Norma Agama b.) Gaya Hidup Yang Semakin Bebas c.) Kurangnya komunikasi dan Pengendalian Diri Yang Rendah. 2.) Dampak Hukum yang timbul dari perceraian yang disebabkan oleh kekerasan dalam rumah tangga dalam hukum materil pada dasarnya tidak mengatur secara spesifik tentang alasan-alasan perceraian dari berbagai problematika sehingga pada perinsipnya perceraian yang disebabkan oleh kekerasan dalam rumah tangga sama dengan perkara perceraian lainnya namun biasanya dalam ijtihad seorang hakim perceraian yang disebabkan oleh kekerasan dalam rumah tangga berpengaruh terhadap siapa yang berhak memiliki hak asuh anak, bagi pelaku kekerasan dalam ruamh tangga biasanya dibebankan tidak memiliki hak asuh anak dengan pertimbangan kemaslahatan kehidupan anak kedepa

    Effect of drought stress on growth, proline and antioxidant enzyme activities of upland rice

    Get PDF
    Responses of eight upland rice (Oryza sativa L.) varieties subjected to different drought levels were investigated in laboratory to evaluate eight local upland rice varieties against five drought levels (0, -2, -4, -6, and -8 bars) at germination and early seedling growth stage of plant development. Data were analyzed statistically for growth parameters; shoot length, root length, and dry matter yield, and biochemical parameters; proline and antioxidant enzymes activity (catalase, superoxide dismutase and peroxidase), were measured. Experiment units were arranged factorial completely randomized design with four replications. The drought-tolerant variety, Pulot Wangi tolerated PEG at the highest drought level (-8 bar) and showed no significantly difference relation to control. However, drought-sensitive variety, Kusam was markedly affected even at the lowest drought level used. Concomitantly, the activity of antioxidant enzymes catalase, peroxidase and superoxide dismutase in the drought-tolerant varieties increased markedly during drought stress, while decreased by drought stress in the drought sensitive variety. Consequently, this led to a marked difference in the accumulation of proline in the upland rice varieties. It may be concluded that the activities of antioxidant enzymes and proline accumulation were associated with the dry mass production and consequently with the drought tolerance of the upland rice varieties
    corecore