Research papers

Floral Biology and Pollination Ecology of Cowpea (Vigna Unguiculata L. Walp)

Olugbenga Ebenezer Ige, O. F. Olotuah, V. Akerele

Studies on the floral biology and pollination ecology of three varieties of cowpea (Vigna unguiculata L. Walp) were carried out. The varieties studied were Var. Oloyin, Var. Sokoto, and Var. Drum. Cowpea is a self pollinated crop which is encouraged by the arrangements of the floral parts. However, Insects visiting cowpea flowers have been implicated in the movement of pollen from one cowpea plant to another. Flower opening of cowpea begins between 6:00am and 6:30am and closes between 11:30am and 12:00pm. Pollen analysis showed similarities in the pollen morphology of the cowpea varieties. Moreover Var. Drum produced the highest number of pollen grains per flower in terms of pollen productivity.

Biology and novel treatment options for XLA, the most common monogenetic immunodeficiency in man

Rudi W. Hendriks, Robbert G. M. Bredius, Karin Pike‐Overzet, Frank J. T. Staal

INTRODUCTION: X-linked agammaglobulinemia (XLA) is the most common primary immunodeficiency in man, and is caused by a single genetic defect. Inactivating mutations in the Bruton's tyrosine kinase (BTK) gene are invariably the cause of XLA,. XLA is characterized by a differentiation arrest at the pre-B cell stage, the absence of immunoglobulins and recurrent bacterial infections, making it an insidious disease that gradually disables the patient, and can result in death due to chronic lung disease. Current treatment involves prophylactic antibiotics and immunoglobulin infusions, which are non-curative. This disease is a good candidate for curative hematopoietic stem cell (HSC)-based gene therapy, which could correct the B cell and myeloid deficiencies. AREAS COVERED: This paper reviews the basic biology of BTK in B cell development, the clinical features of XLA, and the possibilities of gene therapy for XLA, covering the literature from 1995 to 2010. EXPERT OPINION: Work from various laboratories demonstrates the feasibility of using gene-corrected HSCs to complement the immune defects of Btk-deficiency in mice. We propose that it is timely to start clinical programs to develop stem cell based therapy for XLA, using gene-corrected autologous HSC.

Preliminary study on the aspects of the biology of snakehead fish parachanna obscura (günther) in a Nigerian wetland

BB Bolaji, TU Mfon, DI Utibe

Between October 2000 and March 2001, a preliminary study on the aspects of the biology of Parachanna obscura, was carried out. Sex ratio revealed female preponderance (÷2 = 4.733, df = 1, P < 0.05). There was no variation in sex ratio during the wet season but there were more females than males in the dry season (÷2=4.735, df = 1, p =

The Ecology, Biology and Pathogenesis of Acinetobacter spp.: An Overview

James Hamuel Doughari, Patrick Alois Ndakidemi, Izanne Susan Human, Spinney Benade

Acinetobacter are a major concern because of their rapid development of resistance to a wide range of antimicrobials, and rapid profundity in transformation, surviving desiccation and persisting in the environment for a very long time. The organisms are associated with bacteraemia, pulmonary infections, meningitis, diarrhea and notorious nosocomial infections with mortality rates of 20 to 60%. Transmission is via person-to-person contact, water and food contamination, and contaminated hospital equipment. The increasing virulence and rapid development of multidrug resistance by these organisms highlights the need to search for alternatives for chemotherapy. A poor understanding of the organisms and dearth of information about their occurrence especially in developing countries informed the need for this review paper.

Microwave Engineering

K. T. Mathew

Lecture Notes in Mathematics

Stéphane Crépey, Olivier Guéant, David Hobson, Monique Jeanblanc, Jean‐Michel Lasry, Pierre Louis Lions

Effects of Field Studies on Learning Outcome in Biology

Ajaja O. Patrick

The major purpose of this study was to determine the effects of field experiences on students’ knowledge of process of science and biology achievement. The design of the study was experimental, 2 x 2, pre-test, post-test control group design. The sample of the study consisted of 100 biology students in two intact classes. Four research questions were raised and collapsed to four hypotheses. The first three hypotheses were tested with t-test statistic at 0.05 level of significance. The fourth hypothesis was tested with Pearson Product Moment Correlation Statistic. The major findings of this study included: a significance difference in process of science scores between pre-test and posttest of field trip students; a significant difference in process of science test scores between students exposed to field trip experiences and those who were not exposed; a significant difference in biology achievement test scores between students exposed to field trip experiences and those who were not; and a strong correlation between process of science score and biology achievement score. It was concluded that field trip experiences enhanced students’ understanding of process of science, improved students’ attitude towards biology and significantly influenced their biology achievement.

How wide is the “knowing-doing” gap in invasion biology?

Karen J. Esler, Heidi Prozesky, Gyan Prakash Sharma, Mélodie A. McGeoch

Factors influencing knowledge about childhood autism among final year undergraduate Medical, Nursing and Psychology students of University of Nigeria, Enugu State, Nigeria

Monday N. Igwe, Muideen O. Bakare, Ahamefule O Agomoh, Gabriel M Onyeama, Kevin O Okonkwo

BACKGROUND: Knowledge and awareness about childhood autism is low among health care workers and the general populace in Nigeria. Poor knowledge about childhood autism among final year medical, nursing and psychology students who would form tomorrow's child health care professionals can compromise early recognition and interventions that are known to improve prognosis in childhood autism. Educational factors that could be influencing knowledge about childhood autism among these future health care professionals are unknown. This study assessed knowledge about childhood autism among final year undergraduate medical, nursing and psychology students in south-eastern Nigeria and determined the factors that could be influencing such knowledge. METHODS: One hundred final year undergraduate students were randomly selected from each of the Departments of Medicine, Nursing Science and Psychology respectively of University of Nigeria, Enugu State, Nigeria making a sample size of three hundred. A socio-demographic questionnaire and knowledge about childhood autism among health workers (KCAHW) questionnaire were administered to the students. RESULTS: The total mean score for the three groups of students on the KCAHW questionnaire was 10.67+/-3.73 out of a possible total score of 19, with medical, nursing and psychology students having total mean scores of 12.24+/-3.24, 10.76+/-3.50 and 9.01+/-3.76 respectively. The mean scores for the three groups showed statistically significant difference for domain 1 (p=0.000), domain 3 (p=0.029), domain 4 (p=0.000) and total score (p=0.000), with medical students more likely to recognise symptoms and signs of autism compared to nursing and psychology students. The mean score in domain 2 did not show statistically significant difference among the three groups (p=0.769). The total score on the KCAHW questionnaire is positively correlated with the number of weeks of posting in psychiatry (r=0.319, p=0.000) and the number of weeks of posting in paediatrics (r=0.372, p=0.000). The total score is also positively correlated with the number of credit hours of lectures in psychiatry/abnormal psychology (r=0.324, p=0.000) and the number of credit hours of lectures in paediatrics (r=0.372, p=0.000). The field of study also influenced knowledge about childhood autism (p=0.000). CONCLUSION: Peculiar situation in this environment as signified by inadequate human resources needed in the area of clinical psychology training often times necessitates employing first degree graduates in psychology into clinical positions. This calls for additional exposure of the undergraduate psychology students to training curriculum aimed at improving their early recognition of symptoms of autism spectrum disorders in this environment.

The chemistry of graphene oxide

Daniel R. Dreyer, Sungjin Park, Christopher W. Bielawski, Rodney S. Ruoff

The chemistry of graphene oxide is discussed in this critical review. Particular emphasis is directed toward the synthesis of graphene oxide, as well as its structure. Graphene oxide as a substrate for a variety of chemical transformations, including its reduction to graphene-like materials, is also discussed. This review will be of value to synthetic chemists interested in this emerging field of materials science, as well as those investigating applications of graphene who would find a more thorough treatment of the chemistry of graphene oxide useful in understanding the scope and limitations of current approaches which utilize this material (91 references).

The spectrum of latent tuberculosis: rethinking the biology and intervention strategies

Clifton E. Barry, Helena I. Boshoff, Véronique Dartois, Thomas Dick, Sabine Ehrt, JoAnne L. Flynn, Dirk Schnappinger, Robert…

The Systems Biology Graphical Notation

Nicolas Le Novère, Michael Hucka, Huaiyu Mi, Stuart Moodie, Falk Schreiber, Anatoly Sorokin, Emek Demir, Katja Wegner, Mirit…

Classification and Developmental Biology of Congenital Anomalies of the Hand and Upper Extremity

Paul R. Manske, Kerby C. Oberg

1Washington University School of Medicine, Campus Box 8233, 660 South Euclid Avenue, St. Louis, MO 63110. E-mail address: [email protected] 2Divisions of Pediatric Pathology and Human Anatomy, Department of Surgery, Loma Linda University, 24785 Stewart Street, Room B09c, Loma Linda, CA 92350

Sperm Biology: an Evolutionary Perspective

Alan N. Hodgson

Many-body physics with ultracold gases

Immanuel Bloch, Jean Dalibard, W. Zwerger

This paper reviews recent experimental and theoretical progress concerning many-body phenomena in dilute, ultracold gases. It focuses on effects beyond standard weak-coupling descriptions, such as the Mott-Hubbard transition in optical lattices, strongly interacting gases in one and two dimensions, or lowest-Landau-level physics in quasi-two-dimensional gases in fast rotation. Strong correlations in fermionic gases are discussed in optical lattices or near-Feshbach resonances in the BCS-BEC crossover.

Systems biology towards life in silico: mathematics of the control of living cells

Hans V. Westerhoff

Diet, size and reproductive biology of the silver catfish, Chrysichthys nigrodigitatus (Siluformes: Bagridae) in the Cross River, Nigeria

Benedict Obeten Offem, Yemi Akegbejo Samsons, I. T. Omoniyi

The silver catfish, Chrysichthys nigrodigitatus (Lacépède: 1803) is a highly valued food-fish included among the dominant commercial catches exploited in major rivers of Africa. To provide useful biological data for management, samples were collected monthly between January (2005) and December (2007) in three zones: I: Upper Cross River (grassland), II: Middle Cross River (mixed forest and grassland), and III: Lower Cross River (rainforest)] along 200 km length of the Cross River, Nigeria. Data from 1 248 specimens were processed using: allometric coefficient (b), gonado-somatic index, Fulton's condition factor and diversity indices. Male dominance was observed in all populations; C. nigrodigitatus reached maturity at 11.5 cm (male) and 16.7cm (female) total length. Gonado-somatic index was higher for females with a peak in the early rains. The breeding period was between April and August with mean fecundity ranging between 4522 +/- 1924 eggs and 20321 +/- 5543 eggs. This was directly related to total length and weight by the regression models: F = 2365.88 + 560.22 log L and F = 5025.81 +56.34 log W respectively. Exponential equations for length-weight relationships were Wt = -1.997 Lt(2.206) (Zone I), W = -2.831 Lt(3.040) (Zone II) and Wt = -2.245 Lt(2.995) (Zone III). The mean allometric coefficient (b) showed significant departure from cubic value (negative allometry) for Zone I while Zones II and III showed no difference, indicating isometry. Dominant items in the diet were fish and fish parts constituting 21.6% with Food Richness and Gut Repletion Index of 18 and 100% respectively, in all zones. Diet Breadth of 0.802 (Zone 1), 0.922 (Zone II) and 0.910 (Zone III) indicate a high trophic flexibility that enables switching from one diet to another according to availability. Mean condition factor for males varied from 0.718 +/- 0.117 minimum in Zone I to 0.996 +/- 0.062 maximum in Zone III. Forest inland wetlands (Zone II and III) of Cross River provided better condition for C. nigrodigitatus.

Fluorine in medicinal chemistry

Sophie Purser, Peter R. Moore, Steve Swallow, Véronique Gouverneur

It has become evident that fluorinated compounds have a remarkable record in medicinal chemistry and will play a continuing role in providing lead compounds for therapeutic applications. This tutorial review provides a sampling of renowned fluorinated drugs and their mode of action with a discussion clarifying the role and impact of fluorine substitution on drug potency.

Mussel-Inspired Surface Chemistry for Multifunctional Coatings

Haeshin Lee, Shara M. Dellatore, William M. Miller, Phillip B. Messersmith

We report a method to form multifunctional polymer coatings through simple dip-coating of objects in an aqueous solution of dopamine. Inspired by the composition of adhesive proteins in mussels, we used dopamine self-polymerization to form thin, surface-adherent polydopamine films onto a wide range of inorganic and organic materials, including noble metals, oxides, polymers, semiconductors, and ceramics. Secondary reactions can be used to create a variety of ad-layers, including self-assembled monolayers through deposition of long-chain molecular building blocks, metal films by electroless metallization, and bioinert and bioactive surfaces via grafting of macromolecules.

A second generation human haplotype map of over 3.1 million SNPs

Sarah S. Murray, Dennis G. Ballinger, David R. Cox, David A. Hinds, Laura L. Stuvé, John W. Belmont, Suzanne M. Leal, David …

Photogrammetric Engineering and Remote Sensing

John Nicol, B. King, Quattrochi, D, Dowman, I, Ehlers, M, Xiaoli, D

Invasion biology and conservation biology: time to join forces to explore the links between species traits and extinction risk and invasiveness

Mark van Kleunen, David M. Richardson

Expansion and decline of species are natural phenomena (Levin, 2000). However, owing to the increasing infl uence of humans worldwide, the processes driving expansion and decline have speeded up dramatically. Hence, we have the current biodiversity crisis. Humanmediated forces are making some species rarer (ie, driving them towards extinction) while at the same time making some species expand their ranges (‘invasive’ sensu Richardson et al., 2000). Undisputedly, the immediate causes for extinction of native species and invasiveness of aliens are extrinsic factors, such as habitat destruction and climate change. However, the ultimate causes have to be ecological and life-history characteristics of species (Kotiaho et al., 2005). Therefore, important research directions in conservation biology and invasion biology are the analyses of species traits associated with rarity (Murray et al., 2002) and invasiveness (Pyšek and Richardson, 2007), respectively. The first are important for prioritizing conservation efforts, and the second are important for prioritizing eradication efforts and the development of screening protocols of potential invasiveness of species considered for introduction to other regions. Unravelling the links between species traits and extrinsic factors is highly complex, particularly because assessment of the causes of rarity and invasiveness relies mainly on retrospective analyses since large-scale controlled experiments are often not feasible (Richardson et al., 2004). However, with the increasing availability of large, widely accessible databases and analytical approaches (eg, Wilson et al., 2007), it is becoming easier to test which traits are associated with rarity and invasiveness, and under which conditions.

Research Methods in Education

Louis Cohen, Lawrence Manion, Keith Morrison

This fully updated sixth edition of the international bestseller Research Methods in Education covers the whole range of methods currently employed by educational research at all stages. It is divided into five main parts: the context of educational research; planning educational research; styles of educational research; strategies for data collection and researching; and data analysis. The book also contains references to a comprehensive dedicated website of accompanying materials. The sixth edition includes new material on: complexity theory, ethics, sampling and sensitive educational research experimental research, questionnaire design and administration with practical guidance qualitative and quantitative data analysis, with practical examples internet based research. Research Methods in Education is essential reading for the professional researcher and continues to be the standard text for students and lecturers in educational research. To access the dedicated website of accompanying materials, please visit: www.routledge.com/textbooks/9780415368780.

An Overview of the Biology of the Desiccation-tolerant Resurrection Plant Myrothamnus flabellifolia

John P. Moore, George G. Lindsey, Jill M. Farrant, Wolf F. Brandt

BACKGROUND: Myrothamnus flabellifolia is unique as the only woody resurrection plant. It is an important plant in southern Africa because of its widespread occurrence and usage in African medicine and traditional culture. Many reports have investigated facets of its biology and the mechanisms associated with its desiccation tolerance. SCOPE: The general biology of the woody resurrection plant Myrothamnus flabellifolia is reviewed. The review focuses on the geography and ecology, systematic placement, evolution, morphology and reproductive ecology of M. flabellifolia as well as the wood anatomy and re-filling mechanism. In addition, the desiccation tolerance, ethnobotanical importance and medicinal properties of the plant are reviewed. Also, future research avenues are suggested, in particular the necessity to research the biogeography and systematics of the species and the role of the polyphenols present, as well as the molecular basis of the plant's desiccation tolerance.