Seaweed production: overview of the global state of exploitation,farming and emerging research activity

ABSTRACT

The use of seaweeds has a long history, as does the cultivation of a select and relatively small group of species. This review presents several aspects of seaweed production, such as an update on the volumes of seaweeds produced globally by both extraction from natural beds and cultivation. We discuss uses, production trends and economic analysis. We also focus on what is viewed as the huge potential for growing industrial-scale volumes of seaweeds to provide sufficient, sustainable biomass to be processed into a multitude of products to benefit humankind. The biorefinery approach is proposed as a sustainable strategy to achieve this goal. There are many different technologies available to produce seaweed, but optimization and more efficient developments are still required. We conclude that there are some fundamental and very significant hurdles yet to overcome in order to achieve the potential contributions that seaweed cultivation may provide the world. There are critical aspects, such as improving the value of seaweed biomass, along with a proper consideration of the ecosystem services that seaweed farming can provide, e.g. a reduction in coastal nutrient loads. Additional considerations are environmental risks associated with climate change, pathogens, epibionts and grazers, as well as the preservation of the genetic diversity of cultivated seaweeds. Importantly, we provide an outline for future needs in the anticipation that phycologists around the world will rise to the challenge, such that the potential to be derived from seaweed biomass becomes a reality.     

Comparative leaf anatomy of wild Manihot Mill. species (Euphorbiaceae) from Chapada Diamantina,Bahia, Brazil

The leaf anatomy of nine species of Manihot Mill. has been studied with the objective of finding anatomical features that contribute to our understanding of the taxonomy of the genus. Leaf samples were collected in the field and from herbarium specimens, and standardized methods were used for both light and scanning electron microscopy (SEM). The following species were studied: M. bellidifolia P. Carvalho & M. Martins, M. brachyandra Pax & K. Hoffm., M. caerulescens Pohl, M. diamantinensis Allem, M. elongata sp. nov. ined., M. jacobinensis Müll. Arg. (I), M. jacobinensis Müll. Arg. (II), M. longiracemosa P. Carvalho & M. Martins, M. maracasensis Ule, M. reniformis Pohl, M. tripartita (Spreng) Müll. Arg. and Manihot sp. Anatomically, the analysis revealed differences that indicate the importance of leaf anatomy in the species‐level taxonomy. Presence of fibers in the bundle sheath, and presence or absence of papillae and fibers in the midrib are diagnostic characters. Although these characteristics were not enough to separate all of the species, or to group them into a section, they did show taxonomic importance at the species level. In addition, morphoanatomical differences and geographical distribution support Manihot sp. as a distinct species.     

Ring rotation and anomalous metal atom motion in octamethyl ferrocene and spin-lattice relaxation in octamethyl ferrocenium hexafluorophosphate

The dynamics of the metal atom motion in sym octamethyl ferrocene (OMF) has been elucidated over the temperature range 85≤T≤350 K by ⁵⁷Fe Mössbauer effect spectroscopy, and shows a marked increase in the mean-square-amplitude of vibration at 348 K, some 80° below the melting point of the neat solid. Differential scanning calorimetry shows an endothermic peak at about the same temperature, and ΔH is 1.50 kJ mol⁻¹ and ΔS is 4.31 J mol⁻¹ K⁻¹. Corresponding data for OMF⁺PF₆⁻ can be fitted by a relaxation algorithm and confirm the intra-molecular nature of the transition. The spin-lattice relaxation over the above temperature range is fast compared to the characteristic Mössbauer time scale and can be accounted for by a Raman process in the high temperature limit. The transition at 348 K is associated with the onset of ring rotation/libration in the neat solid.     

Four Anchor Repair of Jersey Finger

BackgroundVarious surgical techniques for treating avulsions of the flexor digitorum profundus tendon at the distal phalanx have been published but no ideal technique has emerged. We introduce a new all-internal 4-anchor flexor tendon repair technique and evaluate outcomes in three clinical cases.MethodsIn this retrospective case series, we reviewed three patients that sustained an avulsion of the flexor digitorum profundus tendon at the distal phalanx. All patients were surgically treated with the four-anchor repair technique. Two titanium anchors were inserted into the distal phalanx and two all-suture anchors were inserted distal to the first set of anchors. The tendon was then attached to these four anchors using a Krackow stitch pattern and the anchors were sown to each other. Active flexion and extension of the proximal and distal interphalangeal joint were measured at 3-month, 12-month, and 5-year follow-up. Postoperative complications were documented.ResultsAll patients achieved excellent clinical outcomes according to assessment criteria. At 3-month follow-up, all patients regained full flexion; two patients had full extension, while one patient was 3 degrees short of full extension. At 12-month follow-up, all patients had full flexion and extension. Five-year follow-up demonstrated the same results with no loss of function, sensation or grip strength. The repairs healed without rupture, and no complications were reported.ConclusionThe 4-anchor flexor tendon repair is a viable surgical technique for zone 1 flexor digitorum profundus tendon repair or reconstruction. Further studies are needed to replicate these promising results and biomechanically validate this technique.Level of Evidence: IV     

Recognition of sickle cell anemia in skeletal remains of children

The present study discusses in detail the osteological changes associated with sickle cell anemia in children and their importance in differential diagnosis. Posterior calcaneal and specific articular surface disruptive metacarpal lesions are diagnostic for sickle cell anemia. Calvarial thickening, tibial and femoral cortical bone thickening, and bowing are of more limited utility in differential diagnosis. Granular osteoporosis, pelvic demineralization and rib broadening are nonspecific. Localized calvarial “ballooning,” previously not described, may have diagnostic significance. Bone marrow hyperplastic response (porotic hyperostosis) in sickle cell anemia produces minimal radiologic changes contrasted with that observed in thalassemia and blood loss/hemolytic phenomenon. Two other issues, the osteological criteria for discriminating among the anemias and the purported relationship between porotic hyperostosis and iron deficiency anemia, are also discussed. There is sufficient information to properly diagnose the four major groups of anemias, and further, to establish that iron deficiency is only indirectly associated with porotic hyperostosis. The hyperproliferative bone marrow response (manifest as porotic hyperostosis) to blood loss or hemolysis exhausts iron stores, resulting in secondary iron deficiency. Am J Phys Anthropol 104:213–226, 1997. © 1997 Wiley-Liss, Inc.     

The elusive petroexoccipital articulation

In the present study, 1,869 skulls from the Hamann-Todd Collection were examined (macroscopically and by radiographs) for closure of the petroexoccipital articulation (jugular synchondrosis). The results demonstrated that the petroexoccipital articulation underwent closure between 20 and 50 years of age in most of the human skulls evaluated. Approximately 7–10% of the human skulls underwent complete union of the petroexoccipital articulation before 20 years of age. In 5–9% of the population, the joint remained completely open. After 50 years of age, there was no increase in the frequency of individuals with complete closure. The frequency of “partial closure” was similar (4–8%) for all age groups (20–25, 30–35, 40–45, 50–55, 60–65, and 70+), excluding the 30–35 year old group (17.5%). The time interval necessary for closure to occur appeared to be very short. No significant differences in closure rates due to ethnic origin, gender, or laterality were noted. The utility of the petroexoccipital articulation as an age estimator is discussed. Am J Phys Anthropol 103:365–373, 1997. © 1997 Wiley-Liss, Inc.     

Enantiomerization of Environmentally Significant Overcrowded Polychlorinated Biphenyls (PCBs)

The rotational barriers of overcrowded PCBs are predicted by ab initio methods including electron correlation, thus settling the controversy between theory and experiment. For 2,2′,3,3′,4,6′-hexachlorobiphenyl ( PCB 132 ), an enantiomerization barrier of 185 kJ/mol is calculated by B3LYP/6-31G*, in excellent agreement with the experimental data. Chirality 9:350–353, 1997. © 1997 Wiley-Liss, Inc.     

Rates and Equilibrium of CuA to heme a electron transfer in Paracoccus denitrificans cytochrome c oxidase

Intramolecular electron transfer between CuA and heme a in solubilized bacterial (Paracoccus denitrificans) cytochrome c oxidase was investigated by pulse radiolysis. CuA, the initial electron acceptor, was reduced by 1-methylnicotinamide radicals in a diffusion-controlled reaction, as monitored by absorption changes at 825 nm, followed by partial restoration of the absorption and paralleled by an increase in the heme a absorption at 605 nm. The latter observations indicate partial reoxidation of the CuA center and the concomitant reduction of heme a. The rate constants for heme a reduction and CuA reoxidation were identical within experimental error and independent of the enzyme concentration and its degree of reduction, demonstrating that a fast intramolecular electron equilibration is taking place between CuA and heme a. The rate constants for CuA --> heme a ET and the reverse heme a --> CuA process were found to be 20,400 s(-1) and 10,030 s(-1), respectively, at 25 degrees C and pH 7.5, which corresponds to an equilibrium constant of 2.0. Thermodynamic and activation parameters of these intramolecular ET reactions were determined. The significance of the results, particularly the low activation barriers, is discussed within the framework of the enzyme's known three-dimensional structure, potential ET pathways, and the calculated reorganization energies.     

IL2/IL21 region polymorphism influences response to rituximab in systemic lupus erythematosus patients

To determine whether the IL2/IL21 region, a general autoimmunity locus, contributes to the observed variation in response to rituximab in patients with systemic lupus erythematosus as well as to analyze its influence in a cohort including other autoimmune diseases. rs6822844 G/T polymorphism at the IL2–IL21 region was analyzed by TaqMan assay in 84 systemic lupus erythematosus (SLE) and 60 different systemic autoimmune diseases Spanish patients receiving rituximab. Six months after the first infusion patients were classified, according to the EULAR criteria, as good responders, partial responders and non-responders. A statistically significant difference was observed in GG genotype frequency between responder (total and partial response) (83.56 %) and non-responder (45.45 %) SLE patients (p = 0.010, odds ratio (OR) = 6.10 [1.28–29.06]). No association with the response was evident in the group of patients with autoimmune diseases other than lupus. Furthermore, when both groups of patients were pooled in a meta-analysis, a reduced statistical significance of the association was observed (p = 0.024, OR = 3.53 [1.06–11.64]). Our results show for a first time that IL2–IL21 region seems to play a role in the response to rituximab in SLE patients but not in other autoimmune diseases.