bluuebunny/crossref_metadata_2025_split huggingface dataset:
Delivering the Aichi target 11: challenges and opportunities for marine areas beyond national jurisdiction
Authors: Rochette Julien , Gjerde Kristina , Druel Elisabeth , Ardron Jeff A. , Craw Alicia , Halpin Patrick , Pendleton Linwood , Teleki Kristian , Cleary Jesse 
Published: November 2014

ABSTRACTIn 2010, Contracting Parties to the Convention on Biological Diversity adopted the so‐called ‘Aichi targets’ in order to achieve global biodiversity conservation. Target 11 specifically provides that ‘by 2020 (…) at least 10 per cent of coastal and marine areas (…) are conserved through effectively and equitably managed, ecologically representative and well‐connected systems of protected areas and other effective area‐based conservation measures’. This objective is currently far from being reached since less than 3% of the ocean has been designated as marine protected areas (MPAs).In areas beyond national jurisdiction (ABNJ) in particular, with less than 0.5% protected, there is no mechanism aimed at creating internationally‐recognized MPAs and the initiatives launched by regional organizations, although promising, have limitations.ABNJ are nevertheless facing increasing human pressures and it is therefore appropriate and pressing to designate a comprehensive and representative network of MPAs in these areas. This paper analyses the current efforts conducted to better conserve marine biodiversity in ABNJ and identifies enabling conditions for meeting the Aichi Target 11. Copyright © 2014 John Wiley & Sons, Ltd.
Migratory marine species: their status, threats and conservation management needs
Authors: Lascelles Ben , Notarbartolo Di Sciara Giuseppe , Agardy Tundi , Cuttelod Annabelle , Eckert Sara , Glowka Lyle , Hoyt Erich , Llewellyn Fiona , Louzao Maite , Ridoux Vincent , Tetley Mike J. 
Published: November 2014

ABSTRACTMigratory marine species (MMS) include many of the world's most charismatic organisms such as marine mammals, seabirds, turtles, sharks, and tuna. Many are now among the most threatened due to the diverse range of pressures they encounter during their extensive movements. This paper shows that 21% of MMS are classified as threatened (i.e. categorized as Critically Endangered, Endangered or Vulnerable). Sea turtles are the most threatened group (85%), followed by seabirds (27%), cartilaginous fish (26%), marine mammals (15%) and bony fish (11%). Taken together 48% of MMS are threatened, Near Threatened or Data Deficient.As well as being threatened they share in common being wide‐ranging animals, travelling through the waters of multiple nations as well as in Areas Beyond National Jurisdiction (ABNJ) during different times of the year. This makes their conservation a challenge, requiring coordinated action by many nations, international organizations, Multilateral Environmental Agreements (MEAs) and other stakeholders if their populations are to recover to healthy levels and be safeguarded into the future.Even though they are wide‐ranging, long‐term studies reveal considerable site fidelity and well‐defined habitats for many species and areas. These sites are prime candidates for enhanced management such as via Marine Protect Area (MPA) designations. However, existing management frameworks do not yet contribute sufficiently to MMS conservation, MPA networks need to be expanded to capture key areas, in many cases through the application of new dynamic management techniques such as time area closures.Data on the distribution, abundance, behaviours and threats faced by many MMS are now available. These data should be used to inform the design of effective management regimes, such as MPAs, both within and beyond national jurisdictions. MEAs should ensure a full complement of MMS are included within species listings, and encourage further action to safeguard their populations.Copyright © 2014 John Wiley & Sons, Ltd.
Developing important marine mammal area criteria: learning from ecologically or biologically significant areas and key biodiversity areas
Authors: Corrigan Colleen M. , Ardron Jeff A. , Comeros‐Raynal Mia T. , Hoyt Erich , Notarbartolo Di Sciara Giuseppe , Carpenter Kent E. 
Published: November 2014

ABSTRACTThis paper explores how criteria to identify important marine mammal areas (IMMAs) could be developed, and nested in existing global criteria. This process would consider 134 species of marine mammals.Particular attention is given to two suites of global criteria to identify areas important for the persistence of marine biodiversity: Ecologically or Biologically Significant Areas (EBSAs) developed through the Convention on Biological Diversity (CBD), and Key Biodiversity Areas (KBAs) in revision through the International Union for the Conservation of Nature (IUCN). They are seen as mutually complementary in the development of IMMAs.The specificities necessary for identifying important areas at scales below the global level may vary according to the region, the biophysical requirements of distinct populations, and available data. Refining and testing the applicability of these global criteria on marine mammals at both regional and national scales will be necessary.Combining area‐based measures with non‐spatial management actions will likely be the optimal approach for ensuring marine mammal persistence given their highly migratory nature and widespread life‐history stages.Capacity to enact IMMAs is strengthened by the existence of professional marine mammal associations and networks, and the recently formed IUCN Marine Mammal Protected Areas Task Force (MMPATF). The MMPATF is planning further development of IMMA criteria through joint work with the International Committee on Marine Mammal Protected Areas (ICMMPA). Copyright © 2014 John Wiley & Sons, Ltd.
A Simultaneous Mixed LQR/H∞ Control Approach to the Design of Reliable Active Suspension Controllers
Authors: Wu Jenq‐Lang 
Published: November 2014

AbstractThis paper is concerned with the synthesis of reliable controllers for quarter‐car active suspension systems. By a simultaneous mixed LQR/H∞ control approach, a static output feedback controller is derived for guaranteeing good suspension performance under possible sensor fault or suspension component breakdown. The considered simultaneous mixed LQR/H∞ control problem is a nonconvex optimization problem; therefore, the linear matrix inequality approach is not applicable. Based on the barrier method, we solve an auxiliary minimization problem to get an approximate solution for the simultaneous mixed LQR/H∞ control problem. Necessary conditions for the local optimum of the auxiliary minimization problem are derived. Moreover, a three‐stage solution algorithm is developed for solving the auxiliary minimization problem. The simulation shows that the obtained static output feedback suspension controllers can improve suspension performance in nominal mode and all considered failure modes.
Conscientiousness is modified by genetic variation in catechol‐O‐methyltransferase to reduce symptom complaints in IBS patients
Authors: Hall Kathryn T. , Tolkin Benjamin R. , Chinn Garrett M. , Kirsch Irving , Kelley John M. , Lembo Anthony J. , Kaptchuk Ted J. , Kokkotou Efi , Davis Roger B. , Conboy Lisa A. 
Published: November 2014

AbstractBackgroundAttention to and perception of physical sensations and somatic states can significantly influence reporting of complaints and symptoms in the context of clinical care and randomized trials. Although anxiety and high neuroticism are known to increase the frequency and severity of complaints, it is not known if other personality dimensions or genes associated with cognitive function or sympathetic tone can influence complaints. Genetic variation in catechol‐O‐methyltransferase (COMT) is associated with anxiety, personality, pain, and response to placebo treatment. We hypothesized that the association of complaint reporting with personality might be modified by variation in the COMT val158met genotype.MethodsWe administered a standard 25‐item complaint survey weekly over 3‐weeks to a convenience sample of 187 irritable bowel syndrome patients enrolled in a placebo intervention trial and conducted a repeated measures analysis.ResultsWe found that complaint severity rating, our primary outcome, was negatively associated with the personality measures of conscientiousness (β = −0.31 SE 0.11, P = 0.003) and agreeableness (β = −0.38 SE 0.12, P = 0.002) and was positively associated with neuroticism (β = 0.24 SE 0.09, P = 0.005) and anxiety (β = 0.48 SE 0.09, P < 0.0001). We also found a significant interaction effect of COMT met alleles (β = −32.5 SE 14.1, P = 0.021). in patients genotyped for COMT val158met (N = 87) specifically COMT × conscientiousness (β = 0.73 SE 0.26, P = 0.0042) and COMT × anxiety (β = −0.42 SE 0.16, P = 0.0078) interaction effects.ConclusionThese findings potentially broaden our understanding of the factors underlying clinical complaints to include the personality dimension of conscientiousness and its modification by COMT.
High Ionic Conductivity in a LiFeO2–LiAlO2 Composite Under H2/Air Fuel Cell Conditions
Authors: Lan Rong , Tao Shanwen 
Published: November 2014

AbstractNew ionic conducting materials for electrolytes for electrochemical devices have been attracting the interest of researchers in energy materials. Here, for the first time, we report a conductive composite with high ionic conductivity derived from an electronic conductor α‐LiFeO2 and an insulator γ‐LiAlO2. High conductivity was observed in the α‐LiFeO2–γ‐LiAlO2 composite when prepared by a solid state reaction method. However, the conductivity enhancement in α‐LiFeO2–γ‐LiAlO2 composite was not observed when the two oxides were mechanically mixed. The α‐LiFeO2–γ‐LiAlO2 composite also exhibits O2− or/and H+ ionic conduction which was confirmed through H2/air fuel cell measurements. An exceptionally high conductivity of 0.50 S cm−1 at 650 °C was observed under H2/air fuel cell conditions. This provides a new approach to discover novel ionic conductors from composite materials derived from electronic conductors.
Strong Emissive Nanofibers of Organogels for the Detection of Volatile Acid Vapors
Authors: Xue Pengchong , Sun Jiabao , Yao Boqi , Gong Peng , Zhang Zhenqi , Qian Chong , Zhang Yuan , Lu Ran 
Published: November 2014

AbstractTwo L‐phenylalanine derivatives with 5,8‐bis(2‐(carbazol‐3‐yl)vinyl)quinoxaline (PCQ) and 5,8‐bis[2‐(carbazol‐3‐yl)]‐2,3‐dimethylquinoxaline (DCQ) as fluorophores were synthesized, and their photophysical properties were measured and compared. The two compounds were found to gelate some organic solvents and self‐assemble into 1D nanofibers in gels. The wet gel of PCQ emitted a weak orange fluorescence, but the DCQ gel had a strong green one. This result can be due to the presence of two methyl groups and the nonplanar conformation of fluorophore in DCQ. The gel film of DCQ also showed significantly stronger fluorescence than that of PCQ. Thus, the wet gel and xerogel film of DCQ were selected to study their sensing properties to acids. The yellow wet gel of DCQ transformed into a brown sol upon the addition of 0.2 equiv trifluoroacetic acid (TFA), accompanied by emission quenching. The xerogel film of DCQ rapidly responded to volatile acids, such as TFA, HCl, and HOAc. The fluorescence of the xerogel film was gradually quenched with increased concentration of volatile acid vapors. The fibrous film exhibited low detection limits for volatile acid. The detection limits of the thin films for TFA, HCl, and HOAc reached 43, 122, and 950 ppb, respectively.
Bioinspired Copper(I) Complexes that Exhibit Monooxygenase and Catechol Dioxygenase Activity
Authors: Arnold Aline , Metzinger Ramona , Limberg Christian 
Published: November 2014

AbstractNew tripodal ligand L2 featuring three different pyridyl/imidazolyl‐based N‐donor units at a bridgehead C atom, from which one of the imidazolyl units is separated by a phenylene linker, was synthesized and investigated with regards to copper(I) complexation. The resulting complex [(L2)Cu]OTf (2OTf), the known complex [(L1)Cu]OTf (1OTf; L1 differs from L2 in that it lacks the phenylene spacer) and [(L3)Cu]OTf (3OTf), prepared from a known chiral, tripodal, N‐donor ligand featuring pyridyl, pyrazolyl, and imidazolyl donors, were tested as catalysts for the oxidation of sodium 2,4‐di‐tert‐butylphenolate (NaDTBP) with O2. Indeed, they mediated NaDTBP oxidation to give mainly the corresponding catecholate and quinone (Q). None of the complexes 1OTf, 2OTf, and 3OTf is superior to the others, as yields were comparable and, if the presence of protons is guaranteed by concomitant addition of the phenol DTBP, the oxidation can also be performed catalytically. For all complexes stoichiometric oxidations under certain conditions (concentrated solutions, high NaDTBP content) were found to also generate products typical for metal‐mediated intradiol cleavage of the catecholate with O2. As shown representatively for 1OTf this dioxygenation sets in at a later stage of the reaction. Initially a copper species responsible for the monooxygenation must form from 1OTf/NaDTBP/O2, and only thereafter is the copper species responsible for dioxygenation formed and consumes Q as substrate. Hence, under these circumstances complexes 1OTf–3OTf show both monooxygenase and catechol dioxygenase activity.
ChemInform Abstract: Crystal Structure, Energy Band and Optical Properties of Dysprosium Monophosphate DyPO4.
Authors: Khadraoui Z. , Bouzidi C. , Horchani‐Naifer K. , Ferid M. 
Published: November 2014

AbstractSingle crystals of DyPO4 are prepared by high temperature solid state reaction of a 1:20 mixture of Dy2O3 and NH4H2PO4 (1273 K, 1 d; controlled cooling).
ChemInform Abstract: Synthesis and Photoluminescence Properties of Microcrystalline Sr2ZnWO6:RE3+ (RE: Eu, Dy, Sm and Pr) Phosphors.
Authors: Dabre K. V. , Park K. , Dhoble S. J. 
Published: November 2014

AbstractMicrocrystalline Sr2ZnWO6:Ln3+ (Ln: Eu, Dy, Sm, Pr) phosphors are prepared by solid state reaction of stoichiometric mixtures of SrCO3, ZnO, H2WO4, and Ln2O3 in air (1250 °C, 4 h).
ChemInform Abstract: Reinvestigation of the Cd—Gd Phase Diagram.
Authors: Reichmann Thomas L. , Ipser Herbert 
Published: November 2014

AbstractThe Cd—Gd equilibrium phase diagram is investigated by powder XRD, SEM, and DTA of samples obtained from melts of the elements (Ta tubes in evacuated silica tubes, <767 °C, 1 d).
ChemInform Abstract: Facile Hydrothermal Synthesis of a Highly Efficient Solar Active Pr6O11—ZnO Photocatalyst and Its Multiple Applications.
Authors: Balachandran Subramanian , Thirumalai Kuppulingam , Swaminathan Meenakshisundaram 
Published: November 2014

AbstractThe title photocatalyst is hydrothermally synthesized from an aqueous suspension containing Zn(NO3)2, Pr6O11, and oxalic acid (autoclave, 120 °C, 48 h) followed by calcination at 450 °C for 4 h.
ChemInform Abstract: Controllable Growth of SnS2/SnO2 Heterostructured Nanoplates via a Hydrothermal‐Assisted Self‐Hydrolysis Process and their Visible‐Light‐Driven Photocatalytic Reduction of Cr(VI).
Authors: Mao Liyuan , Li Jingjing , Xie Yunlong , Zhong Yijun , Hu Yong 
Published: November 2014

AbstractA series of SnS2/SnO2 heterostructured nanoplates with different SnO2 contents are synthesized by self‐hydrolysis of SnS2 nanoplates (obtained from aqueous mixtures of SnCl4 and thiourea, autoclave, 180 °C, 10 h) in the presence of an aqueous citric acid solution (autoclave, 180 °C, 2—24 h).
ChemInform Abstract: Construction of Two‐Dimensional MoS2/CdS p‐n Nanohybrids for Highly Efficient Photocatalytic Hydrogen Evolution.
Authors: Zhang Jian , Zhu Zhenping , Feng Xinliang 
Published: November 2014

AbstractTwo‐Dimensional MoS2/CdS nanohybrids with a sandwich‐like p‐n junction heterostructure, large specific surface area, and decreased band gap are solvothermally prepared from a DMSO suspension of well‐dispersed MoS2 nanosheets (obtained from a mixture of LiBH4 and bulk MoS2 in the molar ratio of 2.5:1 at 350 °C for 3 d) and Cd(OAc)2 (ultrasound, autoclave, 220 °C, 18 h).
ChemInform Abstract: Bi—Zn Bond Formation in Liquid Ammonia Solution: [Bi—Zn—Bi]4‐, a Linear Polyanion that is Iso(valence)‐electronic to CO2.
Authors: Benda Christian B. , Koechner Tobias , Schaeper Raphaela , Schulz Stephan , Faessler Thomas F. 
Published: November 2014

Abstract(III) crystallizes as black block‐shaped crystals in the monoclinic space group C2/c with Z = 4 (single crystal XRD) and contains isolated, linear heteroatomic [Bi—Zn—Bi]4‐ anions.
ChemInform Abstract: K3MoPO7: The First Molybdenum Phosphate with Edge‐Sharing MoO6 Octahedra and PO4 Tetrahedra.
Authors: Luo Siyang , Kang Lei , Lin Zheshuai , Chen Chuangtian 
Published: November 2014

AbstractThe new title compound is synthesized by melting a stoichiometric mixture of K2CO3, MoO3, and K2HPO4 followed by slow cooling.
ChemInform Abstract: Catalytic Asymmetric Synthesis of 8‐Oxabicyclooctanes by Intermolecular [5 + 2] Pyrylium Cycloadditions.
Authors: Witten Michael R. , Jacobsen Eric N. 
Published: November 2014

AbstractAdditionally several stereoselective complexity‐generating transformations of the 8‐oxabicyclooctane products are presented.
ChemInform Abstract: Diheteroaromatic Dianionic Oxy‐Cope Rearrangement Route to the Synthesis of Novel Heterocyclic Compounds.
Authors: Huq C. A. M. A. , Sivakumar S. 
Published: November 2014

AbstractThe π bonds of the two heteroaromatic rings act as a 1,5‐hexadiene system necessary for the oxy‐Cope rearrangement.
ChemInform Abstract: Formation of Four Different Aromatic Scaffolds from Nitriles Through Tandem Divergent Catalysis.
Authors: Kim Ju Hyun , Bouffard Jean , Lee Sang‐gi 
Published: November 2014

AbstractReaction of an in situ generated Reformatsky reagent with nitriles and terminal alkynes furnishes an intermediary zinc bromide complex which gives rise to formation of different aromatic scaffolds depending on catalyst and conditions used in the final step.
ChemInform Abstract: A Chemoselective Oxidation of Monosubstituted Ethylene Glycol: Facile Synthesis of Optically Active α‐Hydroxy Acids.
Authors: Chinthapally Kiran , Baskaran Sundarababu 
Published: November 2014

AbstractUnder optimized conditions, chemoselective and racemization‐free oxidation of enantiopure monosubstituted ethylene glycols such as (I) and (IV) is achieved in good yields using the TEMPO‐NaOCl reagent system.
ChemInform Abstract: Simple, Copper(I)‐Catalyzed Oxidation of Benzylic/Allylic Alcohols to Carbonyl Compounds: Synthesis of Functionalized Cinnamates in One Pot.
Authors: Reddy Alavala Gopi Krishna , Mahendar Lodi , Satyanarayana Gedu 
Published: November 2014

AbstractAn environmentally benign copper(I)‐catalyzed oxidation of activated alcohols to corresponding carbonyl compounds is developed.
ChemInform Abstract: A Reagent for Safe and Efficient Diazo‐Transfer to Primary Amines: 2‐Azido‐1,3‐dimethylimidazolinium Hexafluorophosphate.
Authors: Kitamura Mitsuru , Kato So , Yano Masakazu , Tashiro Norifumi , Shiratake Yuichiro , Sando Mitsuyoshi , Okauchi Tatsuo 
Published: November 2014

AbstractThe title compound, a safe, crystalline, and commercially available substance, is found to be an efficient diazo‐transfer reagent for primary amines, even without the aid of a metal salt such as Cu(II).
ChemInform Abstract: Copper‐Catalyzed Cross‐Coupling of Vinylsiloxanes with Bromoalkynes: Synthesis of Enynes.
Authors: Cornelissen Loic , Lefrancq Maxime , Riant Olivier 
Published: November 2014

AbstractA mild copper‐catalyzed cross‐coupling of vinylsiloxanes with bromoalkynes is presented to give the corresponding enynes.
ChemInform Abstract: Efficient Synthesis of 3H‐Indoles Enabled by the Lead‐Mediated α‐Arylation of β‐Ketoesters or γ‐Lactams Using Aryl Azides.
Authors: Zhou Fei , Driver Tom G. 
Published: November 2014

AbstractA simple protocol for the α‐arylation of various β‐ketoesters and lactam (IX) using 2‐azidoaryllead acetates to yield functionalized aryl azides is developed.
ChemInform Abstract: Highly Stereoselective Synthesis of Cyclopropylphosphonates Catalyzed by Chiral Ru(II)‐Pheox Complex.
Authors: Chanthamath Soda , Ozaki Seiya , Shibatomi Kazutaka , Iwasa Seiji 
Published: November 2014

AbstractA highly stereoselective cyclopropanation of alkenes with diethyl diazomethylphosphonate is achieved in the presence of the Ru(II)‐Pheox complex (RPH) as catalyst.
ChemInform Abstract: The Synthesis of Cyclohexenone Using L‐Proline Immobilized on a Silica Gel Catalyst by a Continuous‐Flow Approach.
Authors: Zhi Cong , Wang Jiaqing , Luo Bin , Li Xinming , Cao Xueqin , Pan Yue , Gu Hongwei 
Published: November 2014

Abstract17 Cyclohexene derivatives of type (III) are prepared by a continuous‐flow approach using L‐proline immobilized on silica gel as catalyst.
ChemInform Abstract: Highly Efficient Gold‐Catalyzed Synthesis of Dibenzocycloheptatrienes.
Authors: Pflaesterer Daniel , Rettenmeier Eva , Schneider Severin , de Las Heras Ruiz Edgar , Rudolph Matthias , Hashmi A. Stephen K. 
Published: November 2014

AbstractApplication of this method is demonstrated by the first total synthesis of Reticuol (VIII).
ChemInform Abstract: Multicomponent, Flow Diazotization/Mizoroki—Heck Coupling Protocol: Dispelling Myths about Working with Diazonium Salts.
Authors: Nalivela Kumara S. , Tilley Michael , McGuire Michael A. , Organ Michael G. 
Published: November 2014

AbstractBased on a detailed study on the stability of aryl diazonium salts, the MeOH/DMF solvent system is defined to be suitable for generation and selective coupling of diazonium salts in the presence of all other reaction components.
ChemInform Abstract: Chemoselective Synthesis of Unsymmetrical Internal Alkynes or Vinyl Sulfones via Palladium‐Catalyzed Cross‐Coupling Reaction of Sodium Sulfinates with Alkynes.
Authors: Xu Yanli , Zhao Jinwu , Tang Xiaodong , Wu Wanqing , Jiang Huanfeng 
Published: November 2014

AbstractThe reaction of ortho‐substituted arylsulfinic acid sodium salts with 3‐phenylpropiolic acid gives β‐keto sulfinones [cf.
ChemInform Abstract: Amberlite IR‐120 Catalyzed, Microwave‐Assisted One‐Pot Synthesis of Amides from Nitriles by Ritter Reaction.
Authors: Ghasemnejad‐Bosra Hassan , Habibzadeh Setareh 
Published: November 2014

AbstractA highly efficient method for the synthesis of α‐arylethyl amides from styrenes and related alcohols using the Ritter reaction is developed.
ChemInform Abstract: Synthesis of allo‐ and epi‐Inositol via the NHC‐Catalyzed Carbocyclization of Carbohydrate‐Derived Dialdehydes.
Authors: Stockton Kieran P. , Greatrex Ben W. , Taylor Dennis K. 
Published: November 2014

AbstractThis describes the synthesis of allo‐inositol (IV) as well as a similar synthesis of epo‐inositol.
ChemInform Abstract: Reductive Coupling Reaction of Aldehydes Using Indium(III) Triflate as the Catalyst.
Authors: Mineno Tomoko , Tsukagoshi Rie , Iijima Tsubasa , Watanabe Kazuki , Miyashita Hiroyuki , Yoshimitsu Hitoshi 
Published: November 2014

AbstractA facile protocol for the conversion of aldehydes into the corresponding symmetrical ethers is developed.
ChemInform Abstract: Preparation of Unsymmetrical Ketones from Tosylhydrazones and Aromatic Aldehydes via Formyl C—H Bond Insertion.
Authors: Allwood Daniel M. , Blakemore David C. , Ley Steven V. 
Published: November 2014

AbstractA convenient procedure for the synthesis of unsymmetrical ketones from bench‐stable tosylhydrazones and aryl aldehydes is reported.
ChemInform Abstract: Silyl Imine Electrophiles in Enantioselective Catalysis: A Rosetta Stone for Peptide Homologation, Enabling Diverse N‐Protected Aryl Glycines from Aldehydes in Three Steps.
Authors: Makley Dawn M. , Johnston Jeffrey N. 
Published: November 2014

AbstractN‐(Trimethylsilyl)imines serve in the bis(amidine)‐catalyzed addition of bromonitromethane with a high degree of enantioselection.
ChemInform Abstract: Efficient One‐Step Synthesis of 4‐Amino Substituted Phthalimides and Evaluation of Their Potential as Fluorescent Probes.
Authors: Kindahl Tomas , Chorell Erik 
Published: November 2014

AbstractThe presented method opens up a possibility of introducing novel 4‐amino substituents on the phthalimide central fragment in combination with varying substituents on the phthalimide nitrogen.