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The natural course of Major Depressive Disorder (MDD) encompasses the occurrence of alternating intervals of major depressive episodes and remission. While several abnormalities in neural circuits related to acute MDD have been identified, the neural mechanisms underlying stable remission remain obscure.
Acute MDD is characterized by increased amygdala and subgenual anterior cingulate cortex (sACC) activation and decreased connectivity between the amygdala and the sACC. Consequently, we expect those regions to be affected during remission.
To determine whether active counter-regulatory mechanisms are implicated in the maintenance of full remission once antidepressant treatment has been discontinued.
Functional and structural magnetic resonance imaging was used to measure brain activation and volume of the amygdala and the sACC. Images were obtained from 38 healthy subjects without any psychiatric life-time diagnosis and 38 gender-matched drug-free remitted MDD patients. Furthermore, correlation analyses were performed with clinical variables.
Patients with rMDD exhibited lower activation in the amygdala and the sACC and increased functional coupling between the amygdala and sACC compared to controls. This connectivity was particularly pronounced in patients characterized by a long cumulated time of depressive episodes. Similarly, structural connectivity results showed increased association between the amygdala and sACC volume in rMDD patients compared to controls.
Remitted MDD is related to neural alterations within a neural circuit encompassing the amygdala and the sACC compared to controls. These findings suggest active counter-regulatory mechanisms likely contributing to the maintenance of remission once treatment has been discontinued.
Tail biting is a major welfare and economic problem in intensive pig production. The objectives of this study were to (1) determine tail lesion prevalence at a German abattoir, (2) test for associations between meat inspection findings and tail lesions, (3) assess the agreement between tail necrosis recorded during meat inspection and scored from pictures and (4) test whether the tail biting management tool ‘Schwanzbeiß-Interventions-Programm’ (SchwIP) had an effect on tail lesion prevalence. A total of three observers scored tail lesions from pictures of 43 328 pigs from 32 farms where SchwIP had been applied, and of 36 626 pigs from 32 control farms. Tail lesions were classified as score 0: no visible lesion, score 1: mild lesion, score 2: severe lesion and score 3: necrosis. In addition, complete loss of tail (CL) was recorded. Tail necrosis was the only tail-related carcase finding recorded by meat inspectors. (1) Tail lesion prevalences in pigs from control farms were 23.6% for score 1, 1.02% for score 2, 0.55% for score 3 and 0.41% for CL. The combined prevalence of any lesion and/or CL was 25.4%. (2) Pleurisy, lung findings, signs of inflammation in the legs, arthritis and abscesses were the most frequent meat inspection findings (prevalences of 8.46%, 8.09%, 2.99%, 0.83% and 0.23%, respectively; n=79 954 pigs). Leg inflammation, arthritis and abscesses were more prevalent in pigs with tail lesions of any degree compared with pigs without tail lesions (3.39% v. 2.83%, 1.06% v. 0.75% and 0.39% v. 0.17%, respectively; all P<0.001, n=79 954 pigs). Pigs with severe tail lesions also had more lung findings (2.00% v. 0.17%, P<0.001). (3) Tail necrosis scored during meat inspection resulted in lower prevalence than scored from pictures (0.22% v. 0.69%; n=79 954 SchwIP and control farm pigs). (4) Although tail lesion prevalence was significantly higher in pigs from SchwIP than in pigs from control farms during the first 3 months (32.2% v. 23.8%, P=0.015), it was not significantly higher during the remainder of the year (22.6 v. 26.9, 24.4 v. 21.4 and 24.0 v. 28.0, second, third and fourth quarters, respectively). In conclusion, meat inspection results in much lower tail lesion prevalences than tail lesion assessment from pictures, even if only the category ‘necrosis’ is compared. Advising farms on tail biting using the management tool SchwIP helped to decrease the prevalence of tail lesions on problem farms.
Radiodontan body elements, some belonging to Peytoia and Hurdia and some unassigned, have been reported from the Langston Formation (Spence Shale Member), Wheeler Formation, and Marjum Formation of the middle Cambrian (Series 3) of Utah. These identifications are reassessed in light of recent work on the morphology of the radiodontan Hurdia. New specimens of Hurdia are identified from the Spence Shale, representing mouthparts (oral cones), cephalic carapace H-elements, frontal appendages, and a single isolated swimming flap. The shape of the H-elements allows H. victoria Walcott, 1912 to be identified from the Spence Shale for the first time. The flap is larger and more complete than any reported from the Burgess Shale and allows for a better understanding of the morphology of Hurdia swimming flaps. A 3D model of a Hurdia frontal appendage indicates that there is only one morph of Hurdia frontal appendage found in both species, and apparent morphological differences between disarticulated appendages reflect a preservational continuum caused by varying oblique angles relative to the seafloor. Peytoia should no longer be reported from the Spence Shale, but its presence is confirmed in the Wheeler and Marjum formations. New mouthparts (oral cones) of Hurdia from the Spence Shale and Peytoia from the Marjum Formation with surface textures of submillimeter-diameter raised nodes are described. These new features have not been observed in material from the Burgess Shale and suggest slight differences in preservation.
Universal screening for postpartum depression is recommended in many countries. Knowledge of whether the disclosure of depressive symptoms in the postpartum period differs across cultures could improve detection and provide new insights into the pathogenesis. Moreover, it is a necessary step to evaluate the universal use of screening instruments in research and clinical practice. In the current study we sought to assess whether the Edinburgh Postnatal Depression Scale (EPDS), the most widely used screening tool for postpartum depression, measures the same underlying construct across cultural groups in a large international dataset.
Ordinal regression and measurement invariance were used to explore the association between culture, operationalized as education, ethnicity/race and continent, and endorsement of depressive symptoms using the EPDS on 8209 new mothers from Europe and the USA.
Education, but not ethnicity/race, influenced the reporting of postpartum depression [difference between robust comparative fit indexes (∆*CFI) < 0.01]. The structure of EPDS responses significantly differed between Europe and the USA (∆*CFI > 0.01), but not between European countries (∆*CFI < 0.01).
Investigators and clinicians should be aware of the potential differences in expression of phenotype of postpartum depression that women of different educational backgrounds may manifest. The increasing cultural heterogeneity of societies together with the tendency towards globalization requires a culturally sensitive approach to patients, research and policies, that takes into account, beyond rhetoric, the context of a person's experiences and the context in which the research is conducted.
A new species, Poecilochaetus anterospinus sp. nov., is
described from the east and south shores of Oahu, Hawaii.
Poecilochaetus anterospinus sp. nov. is unique in the
genus by the presence of noto- and neuropodial spines from chaetiger 11 to
posterior segments. Neuropodial spines on anterior chaetigers are absent in
all other Poecilochaetus species while notopodial spines
are limited to segments preceding the pygidium.
Poecilochaetus cf. koshikiensis,
originally described from Japan, is newly recorded from Hawaii and
apparently widely distributed in the western Pacific and South-east Asian
Seas. Poecilochaetus sp. is distinguished from the other
two species by the distribution of the ampullaceous cirri (7–12) and its
Conflicts, of various sizes and purported purposes, cast a long and dark shadow on the lives of many and on the histories of nations and peoples. Theories of conflict abound – for wars between nations, internal civil conflicts, and terrorist operations – primarily based on national or group leaders convincing followers to take up a fight for some purpose, noble (to advance an idea, a religion, a culture, a form of government) or otherwise (to appropriate). While leaders, on occasion, do profit from conflict, they do so less often than they might ever imagine. Indeed, leaders, depending on institutional constraints, can separate the spoils of war (land, resources) from the dim costs of war.
The men and women who conduct the battles, however, can seldom avoid the costs of war, and so are fully saddled with the loss of life, limb, loved ones, livelihood, and way of life. Nor are the soldiers’ interests fully reflected in the interests of those who make the decision to initiate, continue or to change the course of battle. In his famous letter to his World War I commanding officer, Lt. Siegfried Sassoon of the Royal Welch Fusiliers, wrote:
I believe that the war upon which I entered as a war of defence and liberation has now become a war of agression [sic] and conquest. . . . I have seen and endured the sufferings of the troops and I can no longer be a party to prolonging these sufferings for ends which I believe to be evil and unjust. I am not protesting against the conduct of the war, but against the political errors and insincerities for which the fighting men are being sacrificed. On behalf of those who are suffering now, I make this protest against the deception which is being practised upon them; also I believe it may help to destroy the callous complacency with which the majority of those at home regard the continuance of agonies which they do not share and which they have not enough imagination to realise. July, 1917
It is becoming increasingly clear that in order to generate accurate radiocarbon dates for bone collagen samples it is important to determine a sample-specific background correction to account for the greater complexity and higher number of steps in the pretreatment chemistry of this material. To provide suitable samples for the 14C community, 7 bone samples were obtained from contexts within British gravel quarries, which according to other dating techniques or stratigraphic information, should be of infinite age with respect to 14C. The bones were analyzed at the Oxford Radiocarbon Accelerator Unit (ORAU) and the Scottish Universities Environmental Research Centre (SUERC) to determine their suitability. In this paper, we show that 6 of the samples were indistinguishable from background. Both institutions measured finite ages for sample 387 from Oxey Mead that were statistically indistinguishable. Further work is required to establish whether this is because the bone was intrusive and of a younger age than expected or whether it is contaminated either postdepositionally or in the laboratory. We favor the former explanation because (1) the 2 chemistry laboratories use very different pretreatment schemes, (2) collagen yields were high, and (3) the laboratories produced ages that are in good agreement. The 6 “greater than” age samples will be made available to 14C laboratories to be used as background standards.
Glyphosate-resistant (GR) horseweed management continues to be a challenge in no-till cotton systems in Tennessee and Mississippi. Field studies were conducted in 2009 and 2010 to evaluate saflufenacil in tank mixtures with glyphosate, glufosinate, or paraquat on GR horseweed prior to planting cotton. Saflufenacil and saflufenacil tank mixtures were applied 7 d before planting (DBP). Three broad spectrum herbicides were tank-mixed with saflufenacil at rates of 0, 6.3, 12.5, 25, and 50 g ai ha−1. Saflufenacil at 25 and 50 g ai ha−1 in tank mixture with all three broad-spectrum herbicides provided similar GR horseweed control when compared to the current standard of glyphosate + dicamba. Across all saflufenacil rates, lint cotton yield among the glyphosate, glufosinate, and paraquat tank mixture treatments did not differ from each other. Control of horseweed with 25 or 50 g ha−1 of saflufenacil across all tank mixtures also was not different from the standard of glyphosate + dicamba. Moreover, saflufenacil, on silt loam soil evaluated in this study, showed no more cotton injury than glyphosate applied 7 d or more before planting. Saflufenacil applied alone at 25 g ha−1 provided lower control of GR horseweed than the standard, which translated to lower lint yield compared to the glyphosate + dicamba treatment or saflufenacil with each tank mixture partner. The 12.5 g ha−1 rate of saflufenacil tank mixed with either paraquat or glufosinate provided less horseweed control (< 85%) than if higher rates of saflufenacil were used (> 95%). However, lint cotton yield was not different between these treatments. This research suggests that saflufenacil at 25 g ha−1 is the most optimal rate for tank mixtures with glyphosate, glufosinate, or paraquat. It also reaffirms earlier research that the 25 g ha−1 saflufenacil rate safely can be applied inside the currently labeled 42-d waiting period between a saflufenacil application and cotton planting.
Hypovitaminosis D may be associated with diabetes, hypertension and CHD. However, because studies examining the associations of all three chronic conditions with circulating 25-hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D (1,25(OH)2D) are limited, we examined these associations in the US Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial (n 2465). Caucasian PLCO participants selected as controls in previous nested case–control studies of 25(OH)D and 1,25(OH)2D were included in this analysis. Diabetes, CHD and hypertension prevalence, risk factors for these conditions and intake of vitamin D and Ca were collected from a baseline questionnaire. Results indicated that serum levels of 25(OH)D were low ( < 50 nmol/l) in 29 % and very low ( < 37 nmol/l) in 11 % of subjects. The prevalence of diabetes, hypertension and CHD was 7, 30 and 10 %, respectively. After adjustment for confounding by sex, geographical location, educational level, smoking history, BMI, physical activity, total dietary energy and vitamin D and Ca intake, only diabetes was significantly associated with lower 25(OH)D and 1,25(OH)2D levels. Caucasians who had 25(OH)D ≥ 80 nmol/l were half as likely to have diabetes (OR 0·5 (95 % CI 0·3, 0·9)) compared with those who had 25(OH)D < 37 nmol/l. Those in the highest quartile of 1,25(OH)2D ( ≥ 103 pmol/l) were less than half as likely to have diabetes (OR 0·3 (95 % CI 0·1, 0·7)) than those in the lowest quartile ( < 72 pmol/l). In conclusion, the independent associations of 25(OH)D and 1,25(OH)2D with diabetes prevalence in a large population are new findings, and thus warrant confirmation in larger, prospective studies.
Nanoporous MgAl2O4 particulates with high porosities were successfully prepared from sol-gel reactions, solvent exchange with castor oil and subsequent combustion and calcination at 700 °C. The products were crystalline and semitransparent. Changes in the metal precursor concentrations allowed control of pore volumes from 0.7 to 1.1 cm3/g and average pore sizes from 14 to 19 nm. The specific surface areas are about 200 m2/g regardless of the precursor concentrations. After heating at 1000 °C for 10 hours, the products kept about 70% of their original pore volume and about 60% of the original surface area. Heating at 1100 °C caused a drastic reduction of pore volume and surface area to 40 and 36%, respectively, as the average particle size increased to 23 nm.
A transition of porous structures in monolithic poly(methylsilsesquioxane) (PMSQ, CH3SiO1.5) gels from uniform mesopores to hierarchical pore structures consisting of macro- and mesopores, has been investigated using a sol-gel system containing surfactant Pluronic F127. A broad variation of porous morphology is controlled by changing the concentration of F127. Sufficient concentrations of F127 inhibit the occurrence of macroscopic phase separation of hydrophobic PMSQ condensates and lead to well-defined mesoporous transparent aerogels with high specific pore volume. Mesopores are developed through microscopic phase separation of PMSQ colloid-surfactant complexes in the solvent. Macroscopic phase separation regulates well-defined macropores in the micrometer range on decreasing concentrations of F127, in which microscopic phase separation concurrently takes place in the PMSQ-rich gelling phase after the onset of macroscopic phase separation. Monolithic PMSQ gels with hierarchical macro- and mesopore structures are consequently obtained.
Experiments and analysis have been conducted to characterize flow separators used in applications where heated fluid passes between layers of solid material such as in the manufacturing of gelatinous materials. The Biot number of the configuration is the key parameter, and must be taken into account when optimizing performance. It is shown that most prior work was for low Biot number systems, and the particular configurations under consideration operate at high Biot number. Existing designs developed for lower Biot number (such as membrane filter spacers) are shown to perform poorly for this application. An experimental apparatus was designed and fabricated to quantitatively assess pressure drop through the system using different separation strategies. These results were compared with a simplified two-term model based on the physics of viscous drag in these devices. Channels without separators behave like classical Poiseuille flow. Channels with separators can be modeled with a two-term equation: a baseline Poiseuille term and a form drag term. A variety of separator designs are compared and their overall performance is discussed. We also illustrate the high sensitivity to gap height in all configurations.
We describe organic aerogels derived from multifunctional isocyanates through reaction with water (polyureas), acid andydrides (polyimides) and carboxylic acids (polyamides). All processes are invariably single-step, one-pot and take place at room or slightly elevated temperatures. The resulting materials are robust, their density may vary over a very wide range and their nanomorphology can be either particulate or fibrous, but in all cases they all consist of similarly sized primary particles.
Mesoporous organosilicate materials combine tunable binding characteristics, high surface area, and low materials density with an ordered pore network. Surface modifications provide the potential for incorporation of a variety of functional groups. We have taken advantage of these characteristics for the development of a range of materials to be utilized in various applications. In one approach, porphyrins are incorporated into the materials to provide unique catalytic properties. In these materials, the organosilicate scaffold stabilizes the porphyrin catalyst and facilitates interaction of the catalyst and target. Catalysis can be stimulated through exposure to light or application of an electrical current. The selectivity of the materials can be influenced through choice of organic bridging groups in the organosilicate structure and through selection of the porphyrin component. In addition, a type of molecular imprinting can be applied to provide sites on the pore walls that enhance adsorption selectivity for the target. These materials are directed at the development of self-decontaminating surfaces and coatings. Similar materials characteristics have been utilized in the development of solidphase extraction materials for use in the pre-concentration of nitroenergetic targets from ground and surface water samples. These materials are being incorporated into systems for in situ water quality monitoring. Mesoporous organosilicates can also be applied to the encapsulation of proteins and nucleic acids, stabilizing them for wider application of technologies utilizing these reagents. Modifications to the pore surfaces, in this case, are used to incorporate stabilizing agents such as sugars and proteins which should extend shelf-life and reduce storage restrictions.
There are a lot of synthetic polymers which can be used for controlled drug delivery, however they are not easily accepted by the organism. Also incorporation of drugs into carriers runs under difficult conditions. Therefore scientists have been inclined to use natural-origin polymers, such as proteins and polysaccharides. Some of these promising natural polysaccharidic candidates are alginic acid sodium salt, guar gum and chitosan due to their outstanding merits. They are similar to extracellular matrix having high chemical versatility, good biological performance and cell or enzyme-controlled degradability. Many polysaccharidic hydrogels for drug delivery have already been prepared, but one of their weakness is their short life in dry air conditions; thus, special coating materials are being developed for enhancing their life time.
Alginates were used in the present research for synthesis of organic biodegradable gels by sol-gel process, which were further easily converted to aerogels by supercritical drying. They are safe for use, nontoxic, and derived from renewable sources. Aerogels made of alginate are dry and stable materials, which makes them interesting as a substitute to hydrogels. Alginates undergo reversible gelation in aqueous solution through interaction with divalent cations such as Ca2+, which create ionic inter-chain bridges. Two fundamental methods of ionic cross-linking were used to prepare alginate hydrogels: the diffusion method, where spheres are created and the internal setting method resulting in monoliths. After producing the hydrogel, alcogels were formed by solvent exchange using 100% ethanol. Ethanol was later replaced by supercritical CO2 with supercritical drying (100 bar, 35°C). Aerogels made from natural polysaccharides combine both biocharacteristics and aerogel characteristics such as high porosity and specific surface area, which makes them really attractive in drug delivery applications. The aerogels obtained in present research were therefore studied as drug carriers. The effects of the alginate composition and synthesis method on model drug nicotinic acid release were investigated. The results indicated that by using the internal setting cross-linking method for obtaining aerogels nicotinic acid was released in a more controlled manner. That is why further investigation was done on alginate spherical beads for prolonging their drug release. A multi-step sol-gel process was applied to generate complex aerogels with multi-membranes. First ionically cross-linked spherical cores were obtained by dropwise addition of sodium alginate solution into a CaCl2 solution. These cores were further immersed into alginate solution, filtered through a sieve and dropped into a salt solution again. By repeating the above process, different multi-membrane hydrogels were produced and further converted to aerogels. By adding more membranes around core burst drug release was successfully inhibited.
This article examines, from the energy viewpoint, a new lightweight, slim, high energy efficient, light-transmitting envelope system, providing for seamless, free-form designs for use in architectural projects. The research was based on envelope components already existing on the market, especially components implemented with granular silica aerogel insulation, as this is the most effective translucent thermal insulation there is today. The tests run on these materials revealed that there is not one that has all the features required of the new envelope model, although some do have properties that could be exploited to generate this envelope, namely, the vacuum chamber of vacuum insulated panels (VIP), the monolithic aerogel used as insulation in some prototypes, and reinforced polyester barriers. By combining these three design components — the high-performance thermal insulation of the vacuum chamber combined with monolithic silica aerogel insulation, the free-form design potential provided by materials like reinforced polyester and epoxy resins—, we have been able to define and test a new, variable geometry, energy-saving envelope system.
The copolymerization between TEOS (tetraethoxysilane) and silane derivatives was promoted by the application of high power ultrasound to the precursor liquid mixtures in the same way as in the classical sol-gel method. The specific organic precursor was selected from the silanol-terminated polymer family with different molecular functionality and the inorganic precursor was from the silicon alkoxide family. Ultrasound, through the acoustic cavitation process, influences the formation of a very fine distribution of silica particles and avoids cyclidation of the polymer, thus favoring copolymerization with the inorganic particles and leading to the formation of a highly porous and rubber-like solid aerogel. Creep compliance curves, corresponding to the time-dependent depth response to a step load, are imprint site dependent, with pore, soft and stiff sites discerned. In all cases, an instantaneous elastic deformation is apparent. For longer test times, depending on the imprint sites, elastic deformation and newtonian flow produce the rise and fall of the creep curve. Linear parts of the curve on a log-log scale indicate potential growth with small exponents for the creep compliance level. Isochrones stress-strain diagrams show a superlinear trend and an increase with time, which reveals the nonlinear viscoelasticity of these hybrid aerogels. The elasto-plastic response to creep can be tuned by the molecular functionality of the different silane derivatives studied.
Aerogels are regarded as ideal candidates for the design of functional nanocomposites containing supported metal or metal oxide nanoparticles. The large specific surface area together with the open pore structure enables aerogels to effectively host finely dispersed nanoparticles up to the desired loading, to provide nanoparticle accessibility and/or to prevent nanoparticle agglomeration, as required to supply their specific functionalities.
The preparation of highly porous nanocomposite aerogels containing magnetic metal, alloy or metal oxide nanoparticles dispersed into amorphous silica, with high purity and homogeneity, was successfully achieved by a novel sol-gel procedure involving urea-assisted co-gelation of the precursor phases. This method allows fast gelation, giving rise to aerogels with 97% porosity, and it is very versatile allowing to vary composition, loading and average size of the nanoparticles.
The characterization of the morphological and structural features of the nanocomposite aerogels is carried out using different techniques, such as X-ray diffraction, Transmission Electron Microscopy and X-ray Absorption Spectroscopy. The characterization of the magnetic properties is carried out by SQUID magnetometry.