bluuebunny/crossref_metadata_2025 huggingface dataset:
Delta Cell Hyperplasia in Adult Goto-Kakizaki (GK/MolTac) Diabetic Rats
Authors: Alán Lukáš , Olejár Tomáš , Cahová Monika , Zelenka Jaroslav , Berková Zuzana , Smětáková Magdalena , Saudek František , Matěj Radoslav , Ježek Petr
Published: July 2015

Reduced beta cell mass in pancreatic islets (PI) of Goto-Kakizaki (GK) rats is frequently observed in this diabetic model, but knowledge on delta cells is scarce. Aiming to compare delta cell physiology/pathology of GK to Wistar rats, we found that delta cell number increased over time as did somatostatin mRNA and delta cells distribution in PI is different in GK rats. Subtle changes in 6-week-old GK rats were found. With maturation and aging of GK rats, disturbed cytoarchitecture occurred with irregular beta cells accompanied by delta cell hyperplasia and loss of pancreatic polypeptide (PPY) positivity. Unlike the constant glucose-stimulation index for insulin PI release in Wistar rats, this index declined with GK age, whereas for somatostatin it increased with age. A decrease of GK rat PPY serum levels was found. GK rat body weight decreased with increasing hyperglycemia. Somatostatin analog octreotide completely blocked insulin secretion, impaired proliferation at low autocrine insulin, and decreased PPY secretion and mitochondrial DNA in INS-1E cells. In conclusion, in GK rats PI, significant local delta cell hyperplasia and suspected paracrine effect of somatostatin diminish beta cell viability and contribute to the deterioration of beta cell mass. Altered PPY-secreting cells distribution amends another component of GK PI’s pathophysiology.
A Comprehensive Modeling of a Three-Phase Voltage Source PWM Converter
Authors: Segundo-Ramírez Juan , Peña-Gallardo Rafael , Medina Aurelio , Núñez-Gutiérrez Ciro , Visairo-Cruz Nancy
Published: July 2015

This contribution reports the development of a time domain model of a three-phase voltage source converter (VSC) that can be used in the transient and steady state analysis of nonlinear power systems including their associated closed-loop control schemes. With this proposed model, the original discontinuous nonlinear power system can be transformed into a continuous system, while keeping the underlying harmonic nature of the VSC and avoiding typical and undesirable numerical problems associated with the large derivatives during the switching transitions. The development of this model was based on the dynamic Fourier series of the switching functions under a sinusoidal PWM modulation scheme, which require the calculation of the switching instants at each integration step; the switching instants and the dynamic Fourier series coefficients are calculated by explicit mathematical formulas. The proposed model of the VSC is suitable for the fast computation of the periodic steady state solution through the application of Newton method. Simulations were carried out in order to illustrate the benefits of the proposed VSC model.
On the Optimality of Generic Rate-Based AIMD and AIAD Congestion Control Schemes in Cognitive Radio Sensor Networks
Authors: Esmaeelzadeh Vahid , Berangi Reza
Published: July 2015

Investigating the optimality and the modeling of congestion control schemes is crucial in order to provide quality of service (QoS) for various applications in cognitive radio sensor networks (CRSNs). This paper develops an analytical framework to study the optimality of rate-based generic AIMD and AIAD congestion control schemes. In this way, a congestion model is introduced to describe the congestion behavior of CRSNs. A semi-Markov chain (SMC) is proposed to model the steady-state sending rate distribution of source nodes based on the congestion model. The optimality of generic AIMD and AIAD, based on the proposed models, is analyzed in order to maximize the defined rate-congestion ratio (RCR). The analytical results are verified through various NS2-based simulations in CRSNs.
Treatment of Bifocal Cyst Hydatid Involvement in Right Femur with Teicoplanin Added Bone Cement and Albendazole
Authors: Pazarci Ozhan , Oztemur Zekeriya , Bulut Okay
Published: July 2015

Although bone involvement associated with cyst hydatid is rarely seen, it can cause unintended results such as high recurrence rate, infection, sepsis, or amputation of relevant extremity. Because of this reason, its treatment is difficult and disputed. In the case of bifocal bone cyst hydatid in right femur, along with albendazole treatment, result of resecting cyst surgically and its treatment with teicoplanin with added bone cement is given. In conclusion, since the offered treatment method both supports bone in terms of mechanical aspect and also can prevent secondary infection, the method is thought to be a good and safe treatment approach.
Tolerance of Chemoorganotrophic Bioleaching Microorganisms to Heavy Metal and Alkaline Stresses
Authors: Monballiu Annick , Cardon Nele , Tri Nguyen Minh , Cornelly Christel , Meesschaert Boudewijn , Chiang Yi Wai
Published: July 2015

The bioleaching potential of the bacteriumBacillus mucilaginosusand the fungusAspergillus nigertowards industrial residues was investigated by assessing their response towards various heavy metals (including arsenic, cadmium, cobalt, chromium, nickel, lead, and zinc) and elevated pH. The plate diffusion method was performed for each metal to determine the toxicity effect. Liquid batch cultures were set up for more quantitative evaluation as well as for studying the influence of basicity. Growth curves were prepared using bacterial/fungal growth counting techniques such as plate counting, optical density measurement, and dry biomass determination. Cadmium, nickel, and arsenite had a negative influence on the growth ofB. mucilaginosus, whereasA. nigerwas sensitive to cadmium and arsenate. However, it was shown that growth recovered when microorganisms cultured in the presence of these metals were inoculated onto metal-free medium. Based on the findings of the bacteriostatic/fungistatic effect of the metals and the adaptability of the microorganisms to fairly elevated pH values, it is concluded that both strains have potential applicability for further research concerning bioleaching of alkaline waste materials.
Locally Defined Operators in the Space of Functions of Bounded Riesz-Variation
Authors: Aziz W. , Guerrero J. A. , Maldonado K. , Merentes N.
Published: July 2015

We study the locally defined operator on the spaces of bounded Rieszp-variation functions and we prove that those operators are the Nemytskii operator.
Drug-Induced Liver Injury Is a Major Risk for New Drugs
Authors: Seeff Leonard B.
Published: July 2015

Drug-induced liver injury (DILI), a relatively rare condition, is nevertheless a major reason for not approving a drug in development or for removing one already marketed. With a specific diagnostic biomarker lacking, finding elevated serum enzyme [alanine aminotransferase (ALT), aspartate aminotransferase and alkaline phosphatase] activities remains an initial signal for incipient liver injury. Enzyme elevations alone may not be harmful, but if caused by a drug and followed by jaundice (called ‘Hy's law') there is a high possibility of serious DILI. In 1997 several drugs were approved by the Food and Drug Administration (FDA) of the USA that were later withdrawn from the market for serious liver toxicity. New drugs in development are now required to be monitored for liver injury, and the data is to be considered in the approval decision. A program called e-DISH (evaluation of drug-induced serious hepatotoxicity) was introduced in 2004 to aid medical reviewers to select from all subjects studied those few who show nontrivial liver injury and estimate the most likely cause. The threshold of enzyme elevation comprising a warning for possibly serious DILI is uncertain, although generally accepted as 3-5 times the ‘upper limit of normal'. The new direct-acting antiviral agents for treating chronic hepatitis C virus, which often lead to a reduction of elevated ALTs, mandate that a later increase without viral breakthrough be compared to the new on-treatment level of values. The drug may be discontinued or interrupted for evaluation to exclude other possible causes of liver injury. The FDA has approved no drug since 1997 that has been withdrawn later because of serious hepatotoxicity.
Drug-Induced Liver Injury and Individual Cell Models
Authors: Benesic Andreas , Gerbes Alexander L.
Published: July 2015

Drug-induced liver injury (DILI) is the most common cause of acute liver failure and accounts for the majority of regulatory actions on drugs. Furthermore, DILI is a relevant cause for project terminations in pharmaceutical development. The idiosyncratic form of DILI is especially a threat in late clinical development phases and postmarketing, respectively. Even the occurrence of only a few idiosyncratic DILI cases in late clinical development or postmarketing may suffice to terminate or withdraw an otherwise promising therapy. Despite advances in preclinical assessment of dose-dependent toxicity, idiosyncratic DILI is still a big challenge for in vitro research: it not only requires individualized models but also a huge number of tests. We have developed and investigated MetaHeps®, a technology involving hepatocyte-like cells generated from peripheral monocytes without genetic modifications. These cells exhibit several hepatocyte-like characteristics and show donor-specific activities of drug-metabolizing enzymes. With MetaHeps we have performed in vitro investigations in patients with DILI suspicion. By investigating MetaHeps derived from DILI patients we could show increased in vitro susceptibility to the drugs involved in the individual patients. MetaHeps testing could also rule out DILI and help to identify other causes of acute liver injury. Moreover, MetaHeps identified the causative agent in polymedicated patients. In conclusion, in vitro research of idiosyncratic DILI requires individual cell models which produce results comparable to the clinical situation. We suggest the MetaHeps technology as a novel tool to cope with these challenges of DILI.
Noninvasive Assessment of Liver Fibrosis
Authors: Castera Laurent
Published: July 2015

Background: The prognosis and management of chronic liver diseases greatly depend on the amount and progression of liver fibrosis with the risk of developing cirrhosis. Liver biopsy, traditionally considered as the reference standard for the staging of fibrosis, has been challenged over the past decade by the development of novel noninvasive methodologies. Key Messages: Noninvasive methods rely on two different but complementary approaches: a ‘biological' approach based on the dosage serum biomarkers, and a ‘physical' approach based on the measurement of liver stiffness using transient elastography (TE). There are two clinically relevant endpoints for the staging of liver fibrosis: (1) significant fibrosis (indication for antiviral treatment in viral hepatitis B and C), and (2) cirrhosis (indication for screening of esophageal varices and hepatocellular carcinoma). TE (FibroScan®), FibroTest® and APRI have been the most extensively studied and validated methods, mainly in chronic hepatitis C. Combining two unrelated methods, such as TE and biomarkers, is an attractive approach that increases diagnostic performance and limits the drawback of both methodologies. TE appears to be an excellent tool for the early detection of cirrhosis with likely prognostic value in this setting. Thus far, however, it cannot replace upper endoscopy for screening of esophageal varices. The main limitation of TE in clinical practice is the impossibility of obtaining reliable liver stiffness measurements in around 20% of cases, mainly comprising obese patients. Conclusion: An increasing number of reliable noninvasive methods are now available that are widely used in clinical practice, mostly in viral hepatitis, resulting in a significant decrease in the need for liver biopsy.
Clinical Evaluation and Prognosis
Authors: Hernández-Gea Virginia , Berzigotti Annalisa
Published: July 2015

Background: Liver cirrhosis is no longer considered a homogeneous disease, with two different phases now identified: ‘compensated' and ‘decompensated' cirrhosis, in which complications of cirrhosis characterize the latter. Within each phase, different stages and predictors should be recognized in order to correctly stratify the prognosis and individualize possible therapeutic options. Key Messages: In compensated cirrhosis the presence of clinically significant portal hypertension [CSPH = hepatic venous pressure gradient (HVPG) ≥10 mm Hg] constitutes the most important independent predictor of several relevant clinical endpoints (formation of esophageal varices; first clinical decompensation). An optimal HVPG response to medical therapy of portal hypertension (HVPG reduction <12 mm Hg or ≥20% vs. the pretreatment value, responders) has been consistently linked to a decrease in the risk of variceal bleeding both in primary and secondary prophylaxis, and to a decrease in the risk of presenting other clinical decompensating events. Furthermore, in patients undergoing secondary prophylaxis of variceal bleeding, being an HVPG responder is associated with an improved survival. HVPG also maintains an independent prognostic value in patients with decompensated cirrhosis. Noninvasive alternatives to HVPG for the prediction of CSPH have been investigated; liver stiffness by transient elastography and the combination of liver stiffness, spleen size by ultrasound and platelet count are currently the best methods to noninvasively diagnose CSPH, with an accuracy of about 90%. Additional factors modulate prognosis in cirrhosis. Liver function (albumin, bilirubin, INR) is independently associated with prognosis both in compensated and decompensated cirrhosis, and in the latter phase renal function also plays a central role. Among clinical cofactors, obesity and diabetes are emerging as variables increasing the risk of progression to decompensation and death in cirrhosis. Conclusions: Prognostic stratification in patients with cirrhosis should take into account a complex interplay of several clinical, hemodynamic and biological variables. The present review summarizes the existing evidence regarding prognostic factors in cirrhosis, with particular emphasis on compensated cirrhosis.
Systemic Treatment: Expecting Further Success
Authors: Gazzola Alessia , Reig Maria , Di Donato Roberto , Bruix Jordi
Published: July 2015

From its approval in 2008, sorafenib is the recommended treatment option for advanced-stage patients and its safety and efficacy has been confirmed by several studies. However, its mechanism of action is not completely understood and many efforts have been dedicated to investigating possible treatment response predictors. Dermatological adverse events occurring within the first 2 months of treatment are predictors of longer survival, while the same role for hypertension and diarrhea still needs a prospective confirmation. This association is opposite to the strategy of starting at a low dose as it may imply suboptimal drug exposure. In case of radiological progression, the appearance of new extrahepatic metastasis or vascular invasion significantly worsens life expectancy if compared to other patterns of progression. To date no genetic or biologic marker is available to predict response, even if some encouraging results have been reported by the study of polymorphism of VEGF and its receptor. Currently, data are conflicting about the possible predictive role of α-fetoprotein. Due to failure or the progression of therapies for earlier evolutionary stages (BCLC B) some patients in such a clinical profile may be treated with sorafenib. Indeed, almost 50% of the sorafenib-treated patients belong to this class. Patients with severely decompensated liver disease (jaundice, ascites in need of intense diuretic therapy/paracentesis) may not benefit from treatment. The use of sorafenib in the waiting list for liver transplantation is controversial, while its use at an advanced age requires careful evaluation of existing comorbidities that may increase the risk of adverse events. Many strides have been made in the field of hepatocellular carcinoma systemic therapy, and many remain to be realized. Considering the disappointing results of the trials conducted on new agents, a more dynamic interpretation of events together with the development of new strategies is key to enriching new and hopefully more successful trials.
Diagnosis and Treatment of Low-Grade Hepatic Encephalopathy
Authors: Direkze Shamindra , Jalan Rajiv
Published: July 2015

Minimal hepatic encephalopathy (mHE) is common among patients with cirrhotic liver disease and causes significant morbidity and mortality. It may present as cognitive impairment, behavioural changes and, less frequently, with neurological symptoms which make diagnosis of the disease challenging. A history of falls and accidents may also be suggestive of mHE. Diagnosis primarily relies on at least two positive psychometric tests of which the psychometric hepatic encephalopathy score (PHES) is essential. Alternatively, PHES and an electroencephalogram may be used to establish a diagnosis. Biochemical markers of encephalopathy currently have no role in the diagnosis of mHE. Treatment is not always advocated for a diagnosis of mHE but is dependent on the degree of impairment caused by the symptoms. After treatment of other metabolic abnormalities and co-morbidities associated with cirrhosis, more specific treatment for mHE largely relies on therapies used to lower ammonia levels. Laxatives and rifaximin are commonly used in treatment and work through decreasing ammonia absorption from the gut. Other therapies, such as BCAA, LOLA, L-carnitine and phenylbutyrate, modify responses to ammonia as well as enhancing metabolism and excretion. mHE resulting from spontaneous portosystemic shunts or transhepatic intraportal systemic shunts may require ablation or reduction of the shunt. Early detection and appropriate treatment of mHE is important to prevent significant cognitive impairments and progression to overt HE.
Infection as a Trigger for Portal Hypertension
Authors: Steib Christian J. , Schewe Julia , Gerbes Alexander L.
Published: July 2015

Background: Microbial infections are a relevant problem for patients with liver cirrhosis. Different types of bacteria are responsible for different kinds of infections: Escherichia coli and Klebsiella pneumoniae are frequently observed in spontaneous bacterial peritonitis or urinary tract infections, and Streptococcus pneumoniae and Mycoplasma pneumoniae in pulmonary infections. Mortality is up to 4-fold higher in infected patients with liver cirrhosis than in patients without infections. Key Messages: Infections in patients with liver cirrhosis are due to three major reasons: bacterial translocation, immune deficiency and an increased incidence of systemic infections. Nonparenchymal liver cells like Kupffer cells, sinusoidal endothelial cells and hepatic stellate cells are the first liver cells to come into contact with microbial products when systemic infection or bacterial translocation occurs. Kupffer cell (KC) activation by Toll-like receptor (TLR) agonists and endothelial sinusoidal dysfunction have been shown to be important mechanisms increasing portal pressure following intraperitoneal lipopolysaccharide pretreatment in cirrhotic rat livers. Reduced intrahepatic vasodilation and increased intrahepatic vasoconstriction are the relevant pathophysiological pathways. Thromboxane A2 and leukotriene (LT) C4/D4 have been identified as important vasoconstrictors. Accordingly, treatment with montelukast to inhibit the cysteinyl-LT1 receptor reduced portal pressure in cirrhotic rat livers. Clinical studies have demonstrated that activation of KCs, estimated by the amount of soluble CD163 in the blood, correlates with the risk for variceal bleeding. Additionally, intestinal decontamination with rifaximin in patients with alcohol-associated liver cirrhosis reduced the portal pressure and the risk for variceal bleeding. Conclusions: TLR activation of nonparenchymal liver cells by pathogens results in portal hypertension. This might explain the pathophysiologic correlation between microbial infections and portal hypertension in patients with liver cirrhosis. These findings are the basis for both better risk stratifying and new treatment options, such as specific inhibition of TLR for patients with liver cirrhosis and portal hypertension.
Role of Infections in Acute-on-Chronic Liver Failure
Authors: Moreau Richard
Published: July 2015

Patients with cirrhosis are prone to developing bacterial infections. Moreover, bacterial infection is the most common identifiable trigger of acute-on-chronic liver failure (ACLF), which is characterized by organ failures and a high risk of death. There is evidence of an excessive immune response of the host as a major mechanism leading to the development of organ failures in patients with cirrhosis. However, a role for direct tissue damage caused by bacterial toxins and virulence factors cannot be excluded. Failed tolerance mechanisms may also contribute to organ failures, although the involved mechanisms are unclear. A proportion of patients with infection-related ACLF have a prolonged stay in the intensive care unit. These patients have immune suppression, increased risk of superinfection and poor outcome. Immune suppression might be a consequence of the first infection episode that has led patients to be admitted to hospital.
Antiviral Therapy in Hepatitis B Virus-Associated Liver Cirrhosis
Authors: Boettler Tobias , Thimme Robert
Published: July 2015

Background: Chronic hepatitis B virus (HBV) infection is a major risk factor for the development of liver cirrhosis and hepatocellular carcinoma (HCC). Key Messages: In patients with advanced liver fibrosis or liver cirrhosis, antiviral therapy is mandatory to slow down, halt or reverse disease progression and possibly reduce the risk of HCC development. As in patients without advanced fibrosis, PEG-interferon and nucleoside/nucleotide analogues (NUCs) are available for antiviral therapy. NUC therapy should be performed indefinitely as the rates of HBs-Ag loss are low. Entecavir or tenofovir should be preferred due to their strong antiviral potency and their high barrier to resistance. PEG-interferon therapy can be administered to patients with compensated liver disease but should not be offered to patients with signs of hepatic decompensation. Conclusions: Antiviral therapy in chronic HBV infection can reduce liver fibrosis and even revert overt cirrhosis. Whether it also reduces the risk of HCC development in cirrhotic patients remains elusive and might vary in different countries and ethnicities.
Audiometric Results of Open Cavity Tympanomastoidectomy in Advanced Attic Cholesteatoma
Authors: Minovi Amir , Dombrowski Tobias , Shahpasand Shabnam , Dazert Stefan
Published: July 2015

In this retrospective study, we evaluated the audiometric results after using the retrograde mastoidectomy technique with open mastoid cavity for the removal of extended attic cholesteatomas. The described technique was used for cholesteatoma removal in 168 adult patients with an average follow-up time of 12 months. Due to cholesteatoma extension far into the mastoid, the disease was eradicated by the canal wall down (CWD) technique with the creation of an open mastoid cavity. Primary surgery was carried out in 47% of ears, with the remaining 53% representing revision surgery. In all cases, a classical CWD with an open mastoid cavity and partial obliteration with cartilage was created. A dry ear was achieved in 94% of cases. A postoperative air-bone gap ≤20 dB was achieved in 42.9% of the operated ears. 9.3% (n = 15) of the operated ears showed a postoperative air-bone gap >30 dB. Important factors leading to significantly better hearing restoration were an intact malleus, the use of alloplastic titanium prostheses and primary surgery. Although most cholesteatomas nowadays can be eradicated with the canal wall up technique, in far advanced cholesteatomas, the CWD technique can be applied with acceptable postoperative hearing results.
Effect of a β-Hydroxyphosphonate Analogue of L-Carnitine on Insulin-Sensitive and Insulin-Resistant 3T3-L1 Adipocytes
Authors: Avalos-Soriano Anaguiven , De la Cruz-Cordero Ricardo , López-Martínez Francisco Josue , Rosado Jorge L. , Duarte-Vázquez Miguel Ángel , Garcia-Gasca Teresa
Published: July 2015

This study investigated the effect of a β-​hydroxyphosphonate analog of L-carnitine (L-CA) (CAS number: 1220955-​20-3, Component: 1221068-91-2, C12H29NO4PI), (3-Hexanaminium, 1-(dimethoxyphosphinyl)-2-hydroxy-N,N,N,5-​tetramethy-iodide (1:1), (2R, 3S)) on parameters related with type-2 diabetes in an in vitro model. Nontoxic concentrations of L-CA were assayed and compared to commercial L-carnitine effects. L-CA did not affect adipogenesis in normal cells, but an increment of TG accumulation was observed on insulin-resistant adipocytes (80%) when compared with resistant control. L-CA also stimulated glucose analog 2-NBDG uptakes on insulin-resistant adipocytes in a similar way as insulin when compared to insulin-resistant cells. Our results show that the L-CA promoted insulin-like responses on insulin-resistant adipocytes without appreciable pro-adipogenic effect in sensitive adipocytes.
Novel Functions of the Anticoagulant Activated Protein C in Maintaining Skin Barrier Integrity to Impact on Skin Disease
Authors: Xue Meilang , Jackson Christopher John
Published: July 2015

The epidermis is the outermost skin layer and provides the first line of defence against the external environment. Keratinocytes are the most predominant cells in the epidermis and play a critical role in maintaining epidermal barrier function. When the barrier is disrupted any of a number of diseases, such as chronic wounds, psoriasis, pemphigus, atopic dermatitis or toxic epidermal necrolysis, can take hold. Activated protein C (APC) or its precursor, protein C, is abundantly expressed by skin epidermal keratinocytes and stimulates their proliferation and migration, and inhibits apoptosis and inflammation, leading to a healing phenotype. Importantly, APC also increases the barrier function of keratinocytes by promoting expression and cell-cell contact redistribution of tight junction proteins. These cytoprotective properties of APC on epidermal keratinocytes place it as an exciting new therapy for skin disorders associated with the disruption of barrier function and inflammation.
Early Persistent Blood Eosinophilia in Necrotizing Enterocolitis Is a Predictor of Late Complications
Authors: Wahidi Lila S. , Sherman Jan , Miller Mindy M. , Zaghouani Habib , Sherman Michael P.
Published: July 2015

Background: Eosinophils infiltrate intestinal tissue during necrotizing enterocolitis (NEC) and adult bowel diseases. We theorized that epithelial damage causes eosinophilic activation and recruitment at NEC onset. Objective: We studied the relationship between persistent blood eosinophilia and medical or surgical complications during NEC. Methods: NEC cases and controls at MU Children's Hospital (2008-2013) underwent review. A Likert scale measured NEC severity. We utilized an SPSS database for statistical analyses. Results: Of 50 NEC cases, infants in group 1 (n = 15) had eosinophilia <2 days after onset and those in group 2 (n = 25) had NEC but no persistent eosinophilia. Group 3 (n = 46) consisted of controls, i.e. infants without NEC matched for birth weight and gestational age and group 4 (n = 4) of preterm infants with infection and ≤5 days of eosinophilia. Hematologic assessment defined persistent eosinophilia as ≥5% eosinophils for ≥5 days after NEC onset. Absolute eosinophil counts were 2 times higher in group 1 than in group 2 (p = 0.002). The mean duration of eosinophilia was 8 days in group 1 versus 1 day in group 2 (p < 0.001). A Likert score of NEC severity was 3-fold higher in group 1 than in group 2 (p < 0.001). Compared to group 2, group 1 infants were 8 times more likely to have hepatic fibrosis or intestinal strictures. Conclusions: Early persistent blood eosinophilia is not currently a predictor of complications after the onset of NEC. This biomarker identifies immature infants at a high risk for adverse outcomes during NEC convalescence.
An Acute Complication of Ventriculoperitoneal Shunt with Bladder Perforation and Extrusion through the Urethra in a Newborn: Case Report and Review of the Literature
Authors: Mutlu Mehmet , Kader Şebnem , Aslan Yakup , Yazar Uğur , İmamoğlu Mustafa
Published: July 2015

Ventriculoperitoneal shunt (VPS) surgery is a standard procedure for the management of hydrocephalus. Bladder perforation is an extremely rare complication of VPS surgery. Herein, we present for the first time an acute complication of VPS with bladder perforation and extrusion through the urethra in a newborn. We also reviewed the complication of VPS with bladder perforation as reported in the literature.
Malignant Triton Tumor of the Kidney. New Location Not Previously Reported
Authors: Gallego Angel , Pontones Jose Luis , Ramos David , Boronat Francisco
Published: July 2015

Malignant triton tumor (MTT) is a variant of the peripheral nerve sheath tumor. It is very uncommon but shows an aggressive course and limited survival. Half of the cases present symptoms related to neurofibromatosis type 1 disease. There is no standardized treatment, but multimodal approach is the best option. We present the case of a primary MTT located in the kidney, in a 43-year-old woman who received neoadjuvant chemotherapy as first-line treatment followed by surgical resection and adjuvant chemotherapy.
Heartbeats and the Arts: A Historical Connection
Authors: Arozqueta Claudia
Published: July 2015

This article traces the historical relation of heartbeats, science and art. It begins with an outline of historical ideas and science concerning the heart and the arterial pulse that will give better understanding of the intimate relation and differences between both and how early studies of the heart led to the discovery of the pulse and to the early relationship between heartbeats and art. Secondly, it tracks through history the particular interest of artists in making the pulse visible. Devices linked to bodies serve as mediators in artworks that project body mechanisms beyond corporeal limits. The works discussed project heartbeats as metaphors of emotions and life in installations that involve multiple senses.
Lectotypification of Polygonatum franchetii and P. tsinlingense (Asparagaceae)
Authors: Floden Aaron Jennings
Published: July 2015

During systematic studies on Polygonatum Miller (1754: without pagination), the examination of type specimens and protologues revealed several nomenclature issues with regards to typification and priority of two species native to China. Polygonatum tsinlingense Tsui (1949: 135), lacking type designation, was discovered to be an earlier name for P. gracile Li (1966: 252). In addition P. franchetii Hua (1892: 392), also lacking type designation, was described on the basis of a series of three different Farges collections from eastern Sichuan. For both species lectotypes are here selected. Herbarium acronyms follow Thiers (2015).
Taxonomic notes on the Acanthopsis disperma-hoffmannseggiana complex (Acanthaceae, tribe Acantheae), with an interim key to members of the genus
Authors: Steyn Hester Maria , Van Wyk Abraham E
Published: July 2015

Acanthopsis is a taxonomically poorly understood genus confined to arid parts of southern Africa. This contribution is the first detailed assessment of the diversity within the Acanthopsis disperma-hoffmannseggiana complex, the latter of which comprises the bulk of the specimens of the genus represented in herbaria. Species concepts are resolved and the misapplication of names is noted. In addition to the recognition of A. disperma and A. hoffmannseggiana, five new species of Acanthopsis formerly treated under these two names, are described, namely A. tuba and A. ludoviciana (both confined to the Richtersveld, Northern Cape, South Africa), A. adamanticola (endemic to southern Namibia), A. villosa (endemic to Bushmanland, Northern Cape) and A. dispermoides (endemic to the Western Cape, South Africa). The names A. disperma and A. hoffmannseggiana are lectotypified here. An identification key to the members of the Acanthopsis disperma-hoffmannseggiana complex is provided, as well as an interim key to the major artificial groupings in the genus, the taxonomy of some which still needs to be resolved.
Strobilomyces pteroreticulosporus (Boletales), a new species of the S. strobilaceus complex from the Republic of Korea and remarks on the variability of S. confusus
Authors: Antonin Vladimir , Vizzini Alfredo , Ercole Enrico , Leonardi Marco
Published: July 2015

A new species, Strobilomyces pteroreticulosporus, is described based on two recent collections from the Republic of Korea. This new taxon is well characterized by morphological characters, and proved using rpb1 and ITS2 sequences. The variability of size and basidiospore ornamentation of the common species S. confusus is also discussed.
The Response of the South Asian Summer Monsoon to Temporal and Spatial Variations in Absorbing Aerosol Radiative Forcing
Authors: Lee Shao-Yi , Wang Chien
Published: July 2015

Previous studies on the response of the South Asian summer monsoon to the direct radiative forcing caused by anthropogenic absorbing aerosols have emphasized the role of premonsoonal aerosol forcing. This study examines the roles of aerosol forcing in both pre- and postonset periods using the Community Earth System Model, version 1.0.4, with the Community Atmosphere Model, version 4. Simulations were perturbed by model-derived radiative forcing applied (i) only during the premonsoonal period (May–June), (ii) only during the monsoonal period (July–August), and (iii) throughout both periods. Soil water storage is found to retain the effects of premonsoonal forcing into succeeding months, resulting in monsoonal central India drying. Monsoonal forcing is found to dry all of India through local responses. Large-scale responses, such as the meridional rotation of monsoon jet during June and its weakening during July–August, are significant only when aerosol forcing is present throughout both premonsoonal and monsoonal periods. Monsoon responses to premonsoonal forcing by the model-derived “realistic” distribution versus a uniform wide-area distribution were compared. Both simulations exhibit central India drying in June. June precipitation over northwestern India (increase) and southwestern India (decrease) is significantly changed under realistic but not under wide-area forcing. Finally, the same aerosol forcing is found to dry or moisten the July–August period following the warm or cool phase of the simulations’ ENSO-like internal variability. The selection of years used for analysis may affect the precipitation response obtained, but the overall effect seems to be an increase in rainfall variance over northwest and southwest India.
Intraseasonal versus Interannual Measures of Land–Atmosphere Coupling Strength in a Global Climate Model: GLACE-1 versus GLACE-CMIP5 Experiments in ACCESS1.3b
Authors: Lorenz Ruth , Pitman Andrew J. , Hirsch Annette L. , Srbinovsky Jhan
Published: July 2015

Land–atmosphere coupling can strongly affect climate and climate extremes. Estimates of land–atmosphere coupling vary considerably between climate models, between different measures used to define coupling, and between the present and the future. The Australian Community Climate and Earth-System Simulator, version 1.3b (ACCESS1.3b), is used to derive and examine previously used measures of coupling strength. These include the GLACE-1 coupling measure derived on seasonal time scales; a similar measure defined using multiyear simulations; and four other measures of different complexity and data requirements, including measures that can be derived from standard model runs and observations. The ACCESS1.3b land–atmosphere coupling strength is comparable to other climate models. The coupling strength in the Southern Hemisphere summer is larger compared to the Northern Hemisphere summer and is dominated by a strong signal in the tropics and subtropics. The land–atmosphere coupling measures agree on the location of very strong land–atmosphere coupling but show differences in the spatial extent of these regions. However, the investigated measures show disagreement in weaker coupled regions, and some regions are only identified by a single measure as strongly coupled. In future projections the soil moisture trend is crucial in generating regions of strong land–atmosphere coupling, and the results suggest an expansion of coupling “hot spots.” It is concluded that great care needs to be taken in using different measures of coupling strength and shown that several measures that can be easily derived lead to inconsistent conclusions with more computationally expensive measures designed to measure coupling strength.
Water Mass Transformations Driven by Ekman Upwelling and Surface Warming in Subpolar Gyres
Authors: Bell Michael J.
Published: July 2015

The Sverdrup relationship when applied to the Southern Ocean suggests that some isopycnals that are deep in the eastern Pacific will shoal in the Atlantic. Cold waters surfacing in the South Atlantic at midlatitudes would be warmed by the atmosphere. The potential for water mass transformations in this region is studied by applying a three-layer planetary geostrophic model to a wide ocean basin driven by the Ekman upwelling typical of the Southern Ocean surface winds. The model uses a simple physically based parameterization of the entrainment of mass into the surface layer with zonally symmetric atmospheric surface fields to find steady-state subpolar gyre solutions. The solutions are found numerically by specifying suitable boundary conditions and integrating along characteristics. With reasonable parameter settings, transformations of more than 10 Sverdrups (Sv; 1 Sv ≡ 106 m3 s−1) of water between layers are obtained. The water mass transformations are sensitive to the strength of the wind stress curl and the width of the basin and relatively insensitive to the parameterization of the surface heat fluxes. On the western side of the basin where the cold waters are near the surface, there is a large region where there is a local balance between the Ekman pumping and the exchange of mass between layers. Simple formulas are derived for the water mass transformation rates in terms of the difference between the maximum and minimum northward Ekman transports integrated across the basin and the depths of the isopycnal layers on the eastern boundary. The relevance of the model to the Southern Ocean and the Atlantic meridional overturning circulation is briefly discussed.
A Semi-Implicit Version of the MPAS-Atmosphere Dynamical Core
Authors: Sandbach Steven , Thuburn John , Vassilev Danail , Duda Michael G.
Published: July 2015

An important question for atmospheric modeling is the viability of semi-implicit time integration schemes on massively parallel computing architectures. Semi-implicit schemes can provide increased stability and accuracy. However, they require the solution of an elliptic problem at each time step, creating concerns about their parallel efficiency and scalability. Here, a semi-implicit (SI) version of the Model for Prediction Across Scales (MPAS) is developed and compared with the original model version, which uses a split Runge–Kutta (SRK3) time integration scheme. The SI scheme is based on a quasi-Newton iteration toward a Crank–Nicolson scheme. Each Newton iteration requires the solution of a Helmholtz problem; here, the Helmholtz problem is derived, and its solution using a geometric multigrid method is described. On two standard test cases, a midlatitude baroclinic wave and a small-planet nonhydrostatic gravity wave, the SI and SRK3 versions produce almost identical results. On the baroclinic wave test, the SI version can use somewhat larger time steps (about 60%) than the SRK3 version before losing stability. The SI version costs 10%–20% more per step than the SRK3 version, and the weak and strong scalability characteristics of the two versions are very similar for the processor configurations the authors have been able to test (up to 1920 processors). Because of the spatial discretization of the pressure gradient in the lowest model layer, the SI version becomes unstable in the presence of realistic orography. Some further work will be needed to demonstrate the viability of the SI scheme in this case.
Individuals, interactions and institutions: How economic inequality affects organizations
Authors: Bapuji Hari
Published: July 2015

Research in a number of disciplines has shown that high levels of economic inequality adversely affect individuals and societies. Surprisingly, research examining the business consequences of societal level economic inequality is virtually nonexistent. In this article, I present a framework to study how economic inequality affects organizational performance. I suggest that economic inequality indirectly affects organizational performance via human development in the society, and directly via its effects on individual employees and their workplace interactions, as well as via the institutions in which the organizations are embedded. Further, I present a brief research agenda that seeks to illuminate the relationship between economic inequality and management and conclude with an overview of this special issue.
Introductory note
Authors: Edwards Paul K
Published: July 2015

The topic of this special issue is an important and timely one, as all the articles explain. It is also a particularly challenging one for scholars: just how we turn the injunction to connect organizations to inequality into a meaningful research programme is harder than might seem. I am thus particularly grateful to the special issue editors for defining an agenda and producing a set of articles that addresses it. Given that the agenda is challenging, the format of the special issue is slightly unusual. We have the usual five articles on specific topics. Framing them are essays by each of the special issue editors that explain and address different aspects of the wider scholarly challenges of the agenda. Hari Bapuji synthesizes a mass of research that explores the links running from inequality to organizations; he also indicates the contributions of each of the articles. Suhaib Riaz looks at how organizations themselves generate inequality and the intersections between dimensions of inequality and the methodological challenges involved. Each offers a framework with different but potentially complementary ways of thinking about inequality and organizations. In this very short note I offer some very brief further reflections on the connections between agenda and articles.
Playing the Man, Not the Ball
Authors: Waddle Maurice , Bull Peter
Published: July 2015

A challenging question can prompt a variety of responses from politicians in their attempt to save face. Criticising the interviewer is one such tactic identified in previous research. The focus here was on this form of personalisation: responses directed personally at the interviewer, often used as a substitute for a straight answer (i.e., playing the man, not the ball). Sampling online interview videos, our analysis revealed a broad range of personalisations: many critical, but also non-critical, including flattery, banter, and advice to calm down. These tactics are discussed as effective responses, which can disarm, wrong-foot, neutralise, or beguile interviewers, often shifting control towards the politician. Furthermore, personalised rhetoric appears more widespread than previously suggested—featuring in the communicative style of many mainstream British politicians. A new typology of personalisation is proposed, designed to fit within the existing overall equivocation typology for the benefit of future empirical research.
Sorption/release of bioactive species in/from cross-linked poly(ethyleneimine)/poly(N-isopropylacrylamide) films constructed onto solid surfaces
Authors: Bucatariu Florin , Ghiorghita Claudiu-Augustin , Dragan Ecaterina Stela
Published: July 2015

Multilayer thin films are useful materials in the fabrication of controlled drug delivery systems and in controlling drug release processes. Herein, we report the step-by-step deposition of polymer multilayers based on poly(ethyleneimine) (PEI) and poly( N-isopropylacrylamide) (PNIPAAm) mediated by pyromellitic dianhydride (PM), as cross-linker of PEI chains, onto Daisogel silica microparticles. The sorption/release properties of the resulting composite microparticles for indomethacin (IDM), diclofenac sodium salt (DS), and Ponceau SS (PSS) were followed as a function of PM concentration. The sorption properties of the [(PEI-PM)/PNIPAAm] n multilayer films for all anionic species (IDM, DS, and PSS) were influenced by the number of polymer layers and the weight ratio between cross-linker and Daisogel microparticles during the cross-linking steps. It was found that the sorbed amount of anionic compounds increased with the number of polymer layers and with the decrease of PM concentration. The Langmuir and Sips model isotherms fitted well the sorption equilibrium data. The maximum equilibrium sorption capacity ( qm) evaluated by the Langmuir model, at 25°C, was 41 mg IDM g−1 of Daisogel//[(PEI-PM)/PNIPAAm]8.5 and 40 mg PSS g−1 of Daisogel//[(PEI-PM)/PNIPAAm]8.5, for a weight percentage of PM/silica of 0.1% w/w. Cumulative release of IDM was faster and higher than PSS in the first 5 h, while PSS was desorbed with a constant rate for 30 h, supporting a sustained release from Daisogel//[(PEI-PM)/PNIPAAm] n composite microparticles.
Composite materials based on poly(N-isopropylacrylamide-co-methacrylic acid) hydrogels and calcium carbonate
Authors: Doroftei Florica , Mihai Marcela , Sacarescu Liviu , Fundueanu Gheorghe , Simionescu Bogdan C.
Published: July 2015

The synthesis of complex functional materials with thermo- and pH-sensitive tunable properties based on poly( N-isopropylacrylamide- co-methacrylic acid) hydrogels with different porosities and pH-sensitive and biocompatible calcium carbonate (CaCO3) was investigated. To control the composites characteristics, two hydrogles with the same chemical composition but different porosities were used, as well as different methods for crystal growth, namely, the adding protocol of inorganic partners (rapid mixing or alternate dipping) or the carbonate source. The morphology of the new composites was investigated by scanning electron microscopy and the polymorphs content by Fourier transform infrared spectroscopy, as compared to unmodified hydrogels. Information on the interface between organic/inorganic materials, the radii of gyration of the scattering objects, their fractal dimension, and CaCO3 porosity characteristics were obtained by small-angle X-ray scattering.
Synthesis and thermotropic properties of polyazomethines–containing side chain azobenzene moieties
Authors: Cozan Vasile , Iftime Manuela , Sava Ion , Bronnikov Sergei
Published: July 2015

Aromatic polyazomethines–containing azobenzene side groups have been synthesized by solution polycondensation reaction of aromatic dialdehydes bearing flexible spacers between the aromatic rings with aromatic diamines having preformed azobenzene side groups. Thermogravimetric analysis, differential scanning calorimetry, polarized optical microscopy, and wide angle X-ray diffraction have been used to evaluate their thermal and mesomorphic properties. The target polyazomethines showed nematic liquid crystalline phase, large mesophase range, and good thermal stability.