Explore the vast range of titles available.

A \"biography of Rasputin, spiritual guide to the Romanovs and source of great political intrigue, based on many new documents\"-- Provided by publisher.

Mild traumatic brain injury (TBI) is defined as a head trauma resulting in a brief loss of consciousness and/or alteration of mental state. Diagnostic methods to determine the extent of injury to the brain and potential long-term damage in patients are lacking. In this Review, the authors discuss the need for fluid biomarkers of mild TBI, and the potential validation of biomarkers before clinical implementation. Mild traumatic brain injury (TBI), which is defined as a head trauma resulting in a brief loss of consciousness and/or alteration of mental state, is usually benign, but occasionally causes persistent and sometimes progressive symptoms. Whether a threshold for the amount of brain injury and/or individual vulnerability might contribute to the development of these long-term consequences is unknown. Furthermore, reliable diagnostic methods that can establish whether a blow to the head has affected the brain (and in what way) are lacking. In this Review, we discuss potential biomarkers of injury to different structures and cell types in the CNS that can be detected in body fluids. We present arguments in support of the need for further development and validation of such biomarkers, and for their use in assessing patients with head trauma in whom the brain might have been affected. Specifically, we focus on the need for such biomarkers in the management of sports-related concussion, the most common cause of mild TBI in young individuals, to prevent long-term neurological sequelae due to concussive or subconcussive blows to the head. Key Points Biomarkers of neuronal, axonal and astroglial damage could be used to diagnose mild traumatic brain injury (TBI) and predict clinical outcomes of patients with head trauma Such biomarkers could provide important information for medical counselling of at-risk individuals, such as military personnel and concussed athletes Cerebrospinal fluid markers are preferred over peripheral blood markers, owing to their increased proximity to the brain and decreased susceptibility to the confounding effects of various extracerebral factors Ultrasensitive assays are needed for reliable quantification of CNS-specific biomarkers in blood, as their concentrations are below the lower limit of detection by most standard immunoassays Clinical studies of serial biomarker measurements in conjunction with advanced brain imaging during the acute and subacute phases of mild TBI are warranted Longitudinal studies of biomarkers in patients with chronic or progressive symptoms after TBI might help to clarify the pathogenesis and clinical course of chronic traumatic encephalopathy

\"The harrowing, little-known story of the ARA, an American effort to save the newly-formed Soviet Union from a disastrous famine\"-- Provided by publisher.

The link between traumatic brain injury and dementia has long been recognized, and has gained additional prominence through recent high-profile reports of chronic traumatic encephalopathy (CTE) in athletes exposed to repetitive head injury. In this Review, Smith et al . outline the neuropathological features of CTE that are thought to contribute to cognitive impairment, and discuss the work that remains to be done to define CTE as a distinct disease entity. Traumatic brain injury (TBI) has long been recognized to be a risk factor for dementia. This association has, however, only recently gained widespread attention through the increased awareness of 'chronic traumatic encephalopathy' (CTE) in athletes exposed to repetitive head injury. Originally termed 'dementia pugilistica' and linked to a career in boxing, descriptions of the neuropathological features of CTE include brain atrophy, cavum septum pellucidum, and amyloid-β, tau and TDP-43 pathologies, many of which might contribute to clinical syndromes of cognitive impairment. Similar chronic pathologies are also commonly found years after just a single moderate to severe TBI. However, little consensus currently exists on specific features of these post-TBI syndromes that might permit their confident clinical and/or pathological diagnosis. Moreover, the mechanisms contributing to neurodegeneration following TBI largely remain unknown. Here, we review the current literature and controversies in the study of chronic neuropathological changes after TBI. Key Points Traumatic brain injury (TBI) represents the strongest environmental risk factor for dementia Current evidence indicates a possible 'dose' and frequency-dependent association between TBI and risk of neurodegenerative disease The human pathology of survival from TBI is best described as a 'polypathology', featuring amyloid-β, tau and TDP-43 pathologies, together with white matter degradation, neuronal loss and neuroinflammation The chronic pathologies following single and repetitive injuries show similarities, although comparative studies are lacking at present TBI may offer an opportunity for better understanding of the evolution of pathologies in a wider range of neurodegenerative diseases There is an urgent need to extend existing tissue banks dedicated to TBI and establish further networked archives to provide broad international research access

Short carbon fiber-reinforced composite materials produced by large-area additive manufacturing (LAAM) are attractive due to their lightweight, favorable mechanical properties, multifunctional applications, and low manufacturing costs. However, the physical and mechanical properties of short carbon-fiber-reinforced composites 3D printed via LAAM systems remain below expectations due in part to the void formation within the bead microstructure. This study aimed to assess void characteristics including volume fraction and sphericity within the microstructure of 13 wt% short carbon fiber acrylonitrile butadiene styrene (SCF/ABS). Our study evaluated SCF/ABS as a pellet, a single freely extruded strand, a regularly deposited single bead, and a single bead manufactured with a roller during the printing process using a high-resolution 3D micro-computed tomography (µCT) system. Micro voids were shown to exist within the microstructure of the SCF/ABS pellet and tended to become more prevalent in a single freely extruded strand which showed the highest void volume fraction among all the samples studied. Results also showed that deposition on the print bed reduced the void volume fraction and applying a roller during the printing process caused a further reduction in the void volume fraction. This study also reports the void’s shape within the microstructure in terms of sphericity which indicated that SCF/ABS single freely extruded strands had the highest mean void sphericity (voids tend to be more spherical). Moreover, this study evaluated the effect of printing process parameters, including nozzle temperature, extrusion speed and nozzle height above the printing table on the void volume fraction and sphericity within the microstructure of regularly deposited single beads.

\"Combined with over seven hundred documentary photos, [this commemorative volume] tells the story, in words and pictures, of JFK's life and presidency, and depicts his ... vision for America\"--Amazon.com.

Key Points Nanotechnology makes use of the unique properties of objects that function as a unit within the overall size range of 1 to 1,000 nanometres, which is on the same scale as for many biological structures such as antigens, receptors, subcellular components of the immune system and microbes. The engineering of nanoscale compounds by the modification of properties such as nanoparticle size, shape, charge, porosity, surface area and hydrophobicity holds great promise for the development of immune response modulators and vaccines. The enhancement of the immune response by nanoparticles can be achieved through innate immune potentiation or by the enhanced delivery of antigens. Virus-like particles activate the innate immune response via Toll-like receptors and the repetitive display of antigens, whereas nanogels and cationic liposomes are examples of vaccine carriers. The molecular pathways involved in immune activation by nanoparticles are diverse and might include the upregulation of homing receptors such as CC-chemokine receptor 7, co-stimulatory molecules including CD40, CD80 and CD86, as well as increased cytokine production. Enhanced delivery by nanoparticles might induce apoptosis or necrosis. The suppression of the immune response can be achieved through direct immunosuppression or by the delivery of immunosuppressants. Fullerenes have a direct immunosuppressive effect but can also deliver immunosuppressive drugs, as can dendrimers, polymers, and liposomes. The molecular pathways involved in immunosuppression might include increased expression of cyclooxygenase 2, prostangandin E2 and interleukin-10 (IL-10), and apoptosis. The delivery of immunosuppressants results in a decreased response to IL-2 with sirolimus, in the downregulation of nuclear factor-kB with steroids, and in the upregulation of forkhead box P3 (FOXP3), which causes an increased regulatory T cell activity when self antigens are presented. Nanotechnology will continue to provide remarkable insights into the nature of the immune response. The application of nanotechnology to immunology might also affect new strategies to prevent or to treat human diseases. This Review describes the different types of nanotechnologies that can be used to target the immune system. The authors explain how the unique properties of different nanostructures can be used to either enhance or to suppress immune responses, and they discuss the promise of these strategies for developing more effective immunotherapies. Nanotechnology uses the unique properties of objects that function as a unit within the overall size range of 1–1,000 nanometres. The engineering of nanostructure materials, including nanoparticles, nanoemulsions or nanotubules, holds great promise for the development of new immunomodulatory agents, as such nanostructures can be used to more effectively manipulate or deliver immunologically active components to target sites. Successful applications of nanotechnology in the field of immunology will enable new generations of vaccines, adjuvants and immunomodulatory drugs that aim to improve clinical outcomes in response to a range of infectious and non-infectious diseases.

ربيكا فتاة مزرعة صني بروك هي رواية للكاتبة كيت دوجلاس وتتكلم عن الفتاة التي غادرت مزرعتها في مابلوود التي أسمتها صني بروك أو الجداول الشمسية والقصة تحتوي على العديد من مشاهد الحياة في الولايات المتحدة في خلال تلك الفترة والتي تعرض الحياة الاجتماعية والاقتصادية والثقافية لقرى أمريكا وتعتبر القصة من أجمل ما كتبت الكاتبة كيت دوجلاس حيث تم تمثيلها في ثلاثة أفلام أمريكية.

An intriguing aspect of social foraging behaviour is that large groups are often no better at capturing prey than are small groups, a pattern that has been attributed to diminished cooperation (i.e., free riding) in large groups. Although this suggests the formation of large groups is unrelated to prey capture, little is known about cooperation in large groups that hunt hard-to-catch prey. Here, we used direct observations of Yellowstone wolves (Canis lupus) hunting their most formidable prey, bison (Bison bison), to test the hypothesis that large groups are more cooperative when hunting difficult prey. We quantified the relationship between capture success and wolf group size, and compared it to previously reported results for Yellowstone wolves hunting elk (Cervus elaphus), a prey that was, on average, 3 times easier to capture than bison. Whereas improvement in elk capture success levelled off at 2-6 wolves, bison capture success levelled off at 9-13 wolves with evidence that it continued to increase beyond 13 wolves. These results are consistent with the hypothesis that hunters in large groups are more cooperative when hunting more formidable prey. Improved ability to capture formidable prey could therefore promote the formation and maintenance of large predator groups, particularly among predators that specialize on such prey.