Analytic relationship of relative synchronizability to network structure and motifs.

Synchronization phenomena on networks have attracted much attention in studies of neural, social, economic, and biological systems, yet we still lack a systematic understanding of how relative synchronizability relates to underlying network structure. Indeed, this question is of central importance to the key theme of how dynamics on networks relate to their structure more generally. We present an analytic technique to directly measure the relative synchronizability of noise-driven time-series processes on networks, in terms of the directed network structure. We consider both discrete-time autoregressive processes and continuous-time Ornstein-Uhlenbeck dynamics on networks, which can represent linearizations of nonlinear systems. Our technique builds on computation of the network covariance matrix in the space orthogonal to the synchronized state, enabling it to be more general than previous work in not requiring either symmetric (undirected) or diagonalizable connectivity matrices and allowing arbitrary self-link weights. More importantly, our approach quantifies the relative synchronization specifically in terms of the contribution of process motif (walk) structures. We demonstrate that in general the relative abundance of process motifs with convergent directed walks (including feedback and feedforward loops) hinders synchronizability. We also reveal subtle differences between the motifs involved for discrete or continuous-time dynamics. Our insights analytically explain several known general results regarding synchronizability of networks, including that small-world and regular networks are less synchronizable than random networks.

Retroperitoneal fibrosis due to B-cell non-Hodgkin lymphoma: Responding to rituximab!

Retroperitoneal fibrosis is a rare disease manifesting as chronic soft tissue fibrosis in the retroperitoneum, with potential anatomic and/or functional compromise of adjacent organs. It can be primary (idiopathic) or secondary to other conditions such as cancers, autoimmune disorders, or drugs. We report herein a 66-year-old patient with symptomatic retroperitoneal fibrosis leading to bilateral hydronephrosis and renal failure, in whom, after a complex diagnostic work-up and protracted clinical course, a B-cell non-Hodgkin lymphoma in the retroperitoneal space and several vertebral bodies was identified. The patient was treated with radiation therapy and weekly rituximab infusions, with resolution of hydronephrosis and lower back pain. We include a thorough literature review on etiopathogenesis, diagnosis, therapy, and prognosis of retroperitoneal fibrosis. A meticulous search for malignancy is necessary in this rare condition that, if positive, may have significant therapeutic and prognostic implications.

Refractory Small Cell Carcinoma of the Ovary - Hypercalcemic Type (SCCOHT) Treated with Romidepsin and Topotecan: A Case Report and Review of the Literature.

Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT), is a rare yet highly aggressive malignancy with a poor prognosis. Currently, there are no SCCOHT treatment guidelines. After surgery, many patients with SCCOHT receive adjuvant cisplatin and etoposide (CE), based on its efficacy in small cell lung cancer (SCLC). Nonetheless, CE-refractory SCCOHT is still common. Novel therapies (ie, histone deacetylase [HDAC] inhibitors) are being studied as they may target abnormal chromatin remodeling known to be associated with SCCOHT. We present the case of a 21-year-old female with Stage IC SCCOHT status after unilateral oophorectomy. Despite adjuvant CE, the patient developed disease progression. This is the first case report of a patient with CE-refractory SCCOHT treated with second-line topotecan (a topoisomerase-1 inhibitor) and romidepsin (an HDAC inhibitor). Although our patient's SCCOHT further progressed and lead to her death, her story highlights the importance of discovering better therapeutic targets for the treatment of SCCOHT.

Kikuchi-Fujimoto Disease in aYoung African American Male: Are we Seeing a Paradigm Shift in Disease Epidemiology? A Case Report.

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis (HNL), is a rare, self-limiting disease most commonly reported in young Asian women worldwide. We present the case of a 27-year-old African American male who had three weeks of high-grade fevers, night sweats, a 10-pound weight loss, and tender unilateral posterior cervical lymphadenopathy. A complete workup of infectious, rheumatologic, and neoplastic diseases was pursued. Lymph node biopsies revealed histiocyte proliferation with areas of necrosis. These findings were diagnostic of KFD. While KFD has been reported most commonly in young Asian women, in the US, this disease must be considered in both males and females and in diverse ethnicities.

Coronary Vasospasm and Bowel Ischemia in a Patient with Metastatic Gastrointestinal Carcinoid.

We describe a case of a 60-year-old female with a history of metastatic carcinoid disease with liver involvement who developed coronary vasospasm and mesenteric ischemia. The carcinoid syndrome is known for its cardiac involvement most well characterized by fibrous tissue deposits on the endocardium.(1,2) Case reports of coronary artery vasospasm have been previously described and hypothesized to be mediated by vasoactive amines and polypeptides synthesized by the tumor.(3-9) Intestinal ischemia is another reported complication of the carcinoid syndrome and is hypothesized to have a similar mechanism to that of the coronary vasospasm.(10-17) We have reviewed the literature and describe a case of coronary vasospasm and mesenteric ischemia in a patient on octreotide therapy. This is the first case in which we have identified concurrent coronary vasospasm and mesenteric ischemia in a patient with carcinoid disease.

CD5 negative mantle cell lymphoma: a different clinical entity?

We report herein a 77-year-old patient with CD5 negative mantle cell lymphoma (MCL). We further review the existing literature on clinicolaboratory features of this rare MCL subtype. Although most of the patients in the literature (including ours) had advanced stage at diagnosis, splenomegaly, and bone marrow involvement, they displayed prompt and durable responses to conventional treatment. We postulate that CD5 surface antigen expression could have prognostic implications in MCL. Further research and a larger number of patients are necessary in order to validate these findings.

An unusual presentation of Kikuchi-Fujimoto disease.

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a rare, self-limited disease of unknown etiology. This condition is most commonly encountered in Asian and Caucasian females of childbearing age who usually present with cervical lymphadenopathy and fever. Though rarely, KFD has been described in younger African-American females as well. It often mimics more serious conditions such as lymphoma, metastatic solid malignancy, HIV infection, tuberculosis, sarcoidosis, or systemic lupus erythematosus. Although its etiopathogenesis has not been fully elucidated, literature suggests viral or possibly autoimmune components to play a role. We describe a 34-year-old African-American female who presented with constitutional symptoms and polyadenopathy on clinical examination and imaging, of which the portacaval and portahepatis lymph nodes were most prominent. An extensive workup was otherwise unremarkable, and biopsy showed histiocytic necrotizing lymphadenitis. Initially, her clinical condition improved spontaneously, and she required only a short course of oral steroids. Three months later, she relapsed with bilateral cervical adenopathy and constitutional symptoms and was successfully managed again with steroids. Our case is unique with respect to (a) portahepatis and portacaval node enlargement as the dominant adenopathy and (b) her underlying conditions of fibromyalgia and chronic fatigue syndrome.

Plasmablastic haemato-lymphoid neoplasm with a complex genetic signature of Burkitt lymphoma responding to bortezomib.

Plasmablastic lymphoma shares many morphologic features with plasmablastic plasma cell myeloma. The activation of MYC oncogene in these lymphomas may be an important pathogenetic element associated with Epstein-Barr virus infection. We describe herein an elderly man with a plasmablastic lymphoid neoplasm displaying unique morphologic, cytogenetic and clinical features. This case might offer additional insights to the complex but fascinating topic of hybrid haemato-lymphoid neoplasms such as plasmablastic lymphoma-myeloma. In addition, the patient responded to the treatment with bortezomib. Newer antimyeloma agents such as bortezomib have shown promise in the treatment of these neoplasms and should further be explored for their therapy.

Aleukemic leukemia presenting with paranoid psychosis.

Mast cells not only synthesize and release serotonin, but also express and are activated through multiple serotonin receptors. Low blood serotonin level might define a specific subset of patients with systemic mastocytosis (SM) who are more likely to present with neurologic and gastrointestinal complaints. Mast cell leukemia (MCL) is a rare and aggressive type of systemic mastocytosis, and psychiatric manifestations in its course have not been well-characterized. We describe herein a unique patient with a KIT D816V mutation positive a leukemic leukemia variant of systemic mastocytosis with gastrointestinal involvement, presenting with a severe and sustained paranoid delusional illness. While diarrhea improved with the use of histamine H1 and H2 receptor antagonists, the psychosis did not, and the disease followed a dramatic course with a rapidly fatal outcome. As there is paucity of literature, diagnosis of MCL presenting with psychiatric symptoms remains a diagnostic challenge and warrants clinicians to be alert of this rare possibility.

Chest wall stabilization in a patient with severe TBI: A case report.

INTRODUCTION AND IMPORTANCE: Flail chest is a serious complication that may arise secondary to thoracic trauma and is associated with increased morbidity and mortality. In a flail chest, paradoxical chest movement decreases the functional residual capacity, leading to hypoxia, hypercapnia, and atelectasis. Adequate ventilation, fluid and pain management have classically been the cornerstones to flail chest treatment, with operative fixation being utilized in specific cases. Traumatic brain injury (TBI) has historically been believed to be an absolute contraindication for surgical fixation of rib fractures (SSRF); however, emerging studies have shown a favorable prognosis in select patients who underwent SSRF with severe TBI (Glasgow Coma Scale ≤8). CASE PRESENTATION: A 66-year-old male was brought into the Emergency Department by EMS following a traumatic injury that resulted in multiple rib fractures, spinal fractures, and traumatic brain injury. On hospital day 3, the patient underwent SSRF to repair bilateral flail chest. SSRF stabilized cardiopulmonary physiology, improving this patient's hospital course and avoiding the need for a tracheostomy. Herein, we report the successful use of SSRF in a flail chest patient with severe TBI that improved outcomes without evidence of secondary brain injury. CLINICAL DISCUSSION: TBI is a severe condition that often presents with other injuries. Chest wall injuries (CWI) with concurrent TBI remain a significant challenge for clinicians as one set of injuries may exacerbate the other [10]. Through respiratory physiology and predisposition to pneumonia, CWI may lead to prolonged cerebral hypoxia resulting in secondary brain injury-worsening severe TBI. SSRF improves outcomes in polytrauma patients exhibiting CWI with TBI. CONCLUSION: Surgical management of rib fractures has an essential role in select patients with severe TBI. Further research is warranted to improve our understanding of the complex interplay between the physiology of respiratory mechanics and the neurologic system in the trauma population suffering from TBI.

Characterization of polar surface groups on siliceous materials by inverse gas chromatography and the enthalpy-entropy compensation effect.

Surface-modified porous silica is a well-established composite material. To improve its embedding and application behavior, adsorption studies of various probe molecules have been performed using the technique of inverse gas chromatography (IGC). For this purpose, IGC experiments were carried out in the infinite dilution mode on macro-porous micro glass spheres before and after surface modification with (3-mercaptopropyl)trimethoxysilane. To provide information about the polar interactions between probe molecules and the silica surface, in particular, eleven polar molecules have been injected. In summary, the free surface energy for pristine silica ( γ S t o t a l = 229 mJ/m2) and for (3-mercaptopropyl)trimethoxysilane-modified silica ( γ S t o t a l = 135 mJ/m2) indicates a reduced wettability after surface modification. This is due to the reduction of the polar component of the free surface energy ( γ S S P ) from 191 mJ/m2 to 105 mJ/m2. Simultaneously, with the reduction of surface silanol groups caused by surface modification of silica and, therefore, the decrease in polar interactions, a substantial loss of Lewis acidity was observed by various IGC approaches. Experiments with all silica materials have been conducted at temperatures in the range from 90°C to 120°C to determine the thermodynamic parameters, such as adsorption enthalpy ( Δ H a d s ) and adsorption entropy ( Δ S a d s ), using the Arrhenius regression procedure evaluating the IGC data. With the help of the enthalpy-entropy compensation, two types of adsorption complexes are assumed between polar probe molecules and the silica surface because of different isokinetic temperatures. Identical adsorption complexes with an isokinetic temperature of 370°C have been assigned to alkanes and weakly interacting polar probes such as benzene, toluene, dichloromethane, and chloroform. Polar probe molecules with typical functional groups such as OH, CO, and CN, having the ability to form hydrogen bonds to the silica surface, exhibit a lower isokinetic temperature of 60°C. Quantum chemical calculations of the probe molecules on a non-hydroxylated and hydroxylated silica cluster supported the formation of hydrogen bonds in the case of a strong polar adsorption complex with a bonding distance of 1.7 nm-1.9 nm to the silica surface.

Surgical stabilization of rib fracture patients versus nonoperative controls treated by a multidisciplinary team in a single institution.

Introduction: Despite promising evidence, surgical stabilization of rib fractures (SSRF) is not ubiquitously offered in all trauma centers. Some centers struggle with patient selection while some struggle due to surgeon comfort with the technique. To address this issue, our trauma center developed a multidisciplinary SSRF approach between orthopedic and trauma surgery. Methods: This retrospective study compared 43 patients who underwent SSRF at a level 1 trauma center with 43 nonoperatively managed controls. Our study Indications were flail chest with >3 segments; non-flail with severe, bi-cortical displacement of >3 contiguous segments. Main outcome measures included mortality, ICU duration, hospital stay LOS, rates of ventilator-associated pneumonia (VAP) and ventilator days. Results: Results of SSRF included decreases in mortality (2% vs 16.3%; p = 0.03) and in ICU duration. Patients with SSRF had a significantly shorter duration in the ICU than the nonoperative group (8.72 vs 14 days; p = 0.013) but a similar hospital duration (LOS mean, 12.81 vs 15.2; p = 0.29). Less patients in the SSRF group developed VAP but the difference was not significant (2% vs 14%, p = 0.055). Discussion: SSRF patient outcomes supported prior evidence. The tandem approach had benefits as surgeons were able to leverage skills and expertise, increase collaboration between services, and complete more difficult reconstructions. Our experience may serve as a model for trauma centers interested in starting a new program or enhancing current service offerings.

Shift Length and Shift Length Preference Among Acute Care Surgeons.

BACKGROUND: Work hour restrictions have been imposed by the Accreditation Council for Graduate Medical Education since 2003 for medical trainees. Many acute care surgeons currently work longer shifts but their preferred shift length is not known. METHODS: The purpose of this study was to characterize the distribution of the current shift length among trauma and acute care surgeons and to identify the surgeons' preference for shift length. Data collection included a questionnaire with a national administration. Frequencies and percentages are reported for categorical variables and medians and means with SDs are reported for continuous variables. A chi-square test of independence was performed to examine the relation between call shift choice and trauma center level (level 1 and level II), age, and gender. RESULTS: Data from 301 surgeons in 42 states included high-level trauma centers. Assuming the number of trauma surgeons in the United States is 4129, a sample of 301 gives the survey a 5% margin of error. The median age was 43 years (M = 46, SD = 9.44) and 33% were female. Currently, only 23.3% of acute care surgeons work a 12-hour shift, although 72% prefer the shorter shift. The preference for shorter shifts was statistically significant. There was no significant difference between call shift length preference and trauma center level, age, or gender. CONCLUSION: Most surgeons currently work longer than 12-hour shifts. Yet, there was a preference for 12-hour shifts indicating there is a gap between current and preferred shift length. These findings have the potential to substantially impact staffing models.

Gamma flicker triggers attentional selection without awareness.

Gamma band modulations in neural activity have been proposed to mediate attentional processes. To support a causal link between gamma activity and attentional selection, we attempt to evoke gamma oscillations by a 50-Hz subliminal flicker. We find that a subliminal 50-Hz flicker at a target location, before target presentation, speeds up and enhances target detection and discrimination. This effect is specific to the middle of the gamma range because it is not evident at <35-Hz flicker. It requires 300 ms to build up, dissipates within 250 ms of flicker offset, and shows a tendency to invert after 500 ms. The results are discussed in relation to a role for gamma band neural synchrony in the allocation of visual attention.

Negative pressure wound therapy with intermittent irrigation for treatment of post-traumatic giant abscess: A case report.

INTRODUCTION: Negative pressure wound therapy (NPWT), also called vacuum-assisted closure, is an adjunctive therapy used to manage open wounds that apply subatmospheric pressure to the wound surface. The therapeutic effects of NPWT are exerted by stabilizing the wound environment, increasing blood flow, and macro-deformation of wounds that initiate granulation tissue formation. CASE PRESENTATION: We present a case of a 28-year-old Caucasian male who developed a giant non-resolving hepatic abscess secondary to a gunshot wound (GSW) to the upper right abdomen. The abscess was successfully treated with open debridement followed by NWPT with instillation therapy. Significant reduction in abscess diameter and cessation of trauma-induced bile leak was observed following 15 days of wound vac treatment. DISCUSSION: Wound vac treatment was essential in this patient due to the inherent erosive properties of bile that damage surrounding tissue and perpetuate opportunistic growth of pathogenic microbes. Prior to standard NPWT treatment, debridement of devitalized tissues and infection should be managed; however, instillation therapy has permitted NPWT to be used in the presence of infection or as an adjuvant to surgical infection management. CONCLUSION: NPWT is indicated for a wide range of acute and chronic wounds; however, the utilization of NPWT to treat abscesses remains unclear.

Content-Aware Brightness Solving and Error Mitigation in Large-Scale Multi-Projection Mapping.

Projection mapping with inexpensive hardware often suffers from calibration errors that lead to visually compromised results. In this paper, we classify common errors that lead to typical visual artifacts. Based on this classification, we present the first content-aware brightness solver. It is tailored for high GPU performance, yet efficiently hides the most common calibration artifacts. Moreover, it is specifically designed to handle both single and larger networked projection mapping setups with minimal latency.

Interactions of different body parts in peripersonal space: how vision of the foot influences tactile perception at the hand.

The body schema, a constantly updated representation of the body and its parts, has been suggested to emerge from body part-specific representations which integrate tactile, visual, and proprioceptive information about the identity and posture of the body. Studies using different approaches have provided evidence for a distinct representation of the visual space approximately 30 cm around the upper body, and predominantly the hands, termed the peripersonal space. In humans, peripersonal space representations have often been investigated with a visual-tactile crossmodal congruency task. We used this task to test if a representation of peripersonal space exists also around the feet, and to explore possible interactions of peripersonal space representations of different body parts. In Experiment 1, tactile stimuli to the hands and feet were judged according to their elevation while visual distractors presented near the same limbs had to be ignored. Crossmodal congruency effects did not differ between the two types of limbs, suggesting a representation of peripersonal space also around the feet. In Experiment 2, tactile stimuli were presented to the hands, and visual distractors were flashed either near the participant's foot, near a fake foot, or in distant space. Crossmodal congruency effects were larger in the real foot condition than in the two other conditions, indicating interactions between the peripersonal space representations of foot and hand. Furthermore, results of all three conditions showed that vision of the stimulated body part, compared to only proprioceptive input about its location, strongly influences crossmodal interactions for tactile perception, affirming the central role of vision in the construction of the body schema.

Interaction of attention and temporal object priming.

Within a 3 x 3 matrix of 90 degrees corner junctions, detection of a Kanizsa-type square is facilitated when the target display is preceded by a 40-Hz flickering premask of 3 x 3 crosses, with four crosses synchronously oscillating at the subsequent target location. To examine whether this 'synchrony-priming' effect is influenced by, or dependent on, visuo-spatial attention, a spatial-cueing manipulation was introduced. Observers were presented with a visual or acoustic cue which indicated the likely target quadrant. The main finding was that synchrony priming was larger for invalidly, compared with validly, cued locations, and that the priming effect was figural, rather than spatial, in nature (i.e., confined to points associated with the completed boundary, rather than extending to the inner region, defined by the synchronous premask elements). This pattern of effects argues that target processing is expedited not by attracting spatial attention to the primed location, but by the prime expediting (figure-specific) target encoding, as a result of which the target position gains a processing and selection advantage relative to non-primed locations.

Functionalization of porous siliceous materials, Part 2: Surface characterization by inverse gas chromatography.

Surface modification of porous glass beads by ethanol-based 3-mercaptopropyltrimethoxysilane (MPTMS) grafting solutions is directly evidenced by nitrogen adsorption, elemental analysis, thermogravimetry, infrared and 29Si CP MAS NMR spectroscopy. Furthermore, the energetic characterization of the surface is essential to understand comprehensively the physico-chemical interactions between the pristine and MPTMS-modified surface and its gas/liquid-phase environment. In this study, inverse gas chromatography (IGC) is used to characterize the surface properties of porous glass (PG). By means of IGC at infinite dilution (IGC-ID), the dispersive component of the surface energy (γsd), the enthalpy and entropy of adsorption of C6-C10 hydrocarbon probes were determined at temperatures between 30 and 120 °C. The specific component of the surface energy (γssp) at the temperature of 120 °C has been obtained via the Van Oss theory and a least-squares procedure evaluating the IGC data of 8 polar probe molecules collectively. After surface silylation, the total surface energy (γst) decreased from 402 to 255 mJ/m² indicating both a reduced wettability and an increased hydrophobicity of the MPTMS-modified PG. Moreover, the acidity/basicity parameters according to the Van Oss and the Gutmann approach indicated that the acidity of the PG surface decreases by MPTMS grafting. Using n-octane and isopropanol probes, IGC at finite concentration (IGC-FC) was applied to obtain their adsorption isotherms and subsequently the BET specific surface areas. In addition, the surface heterogeneity of the studied PGs was also computed. The energy distribution functions of adsorption sites were monomodal (peak maximum at about 22 kJ/mol) for the n-octane probe, while isopropanol revealed a bimodal distribution function (maxima at about 18 and 25 kJ/mol) on both pristine and MPTMS-modified PG. Furthermore, the proportion of high energy sites (apparently assigned to SiOH groups) has been reduced by surface modification from 65% to only 35% despite a high surface coverage of ˜10 MPTMS species/nm2. These findings are in agreement with the results of 29Si CP MAS NMR measurements and are supported by DFT calculations on the adsorption of isopropanol and n-octane on the surface of a silica cluster model.

Spatial structure affects temporal judgments: evidence for a synchrony binding code.

Visual binding is the process by which the brain groups the elements belonging to one object, whilst segregating them from other scene elements. A computationally parsimonious mechanism of visual binding is the binding-by-synchrony (BBS) hypothesis. According to this hypothesis, detectors that respond to elements of a single object fire in synchrony, while detectors that respond to elements of different objects do not. Current psychophysical and physiological evidence are inconclusive about the role of BBS in the visual integration process. Here we provide psychophysical and computational evidence suggesting that the visual system implements a mechanism that synchronizes response onsets to object parts and attenuates or cancels their latency differences. In three experiments, observers had to judge the synchrony of two flickering Gabor patches embedded in a static Gabor contour, passing through fixation. We found that a smooth contour, as compared to a jagged one, impedes judgments of temporal synchrony between the targets, whilst facilitating non-temporal judgments of contrast on the same targets. We show that the results are consistent with a simple computational model that implements synchronization of responses via lateral interactions, enabling the visual system to pick up objects by synchrony among a temporally diverse background.