bluuebunny/crossref_metadata_2025 huggingface dataset:
A Cross-Cultural Perspective on Motives and Patterns of Brand Recommendation in Social Media
Authors: Kolo Castulus , Widenhorn Stefan , Borgstedt Anna-Lena , Eicher David
Published: March 2018

This article describes how today, social media enable users to comment on brands in a multitude of ways. Although it is undoubted that this can have a substantial influence on the way brands impact on consumers, comparatively little is known about what motivates consumers to recommend brands in social media and whether there are cultural differences therein. This article aims to determine the factors leading to either positive or negative communication about brands on Facebook, YouTube, Twitter, and brand-related blogs based on a representative sample from Germany and the US, each with 1,000 adults. Complementary to an analysis of factors determining a general inclination to recommend, a principal component analysis of the diverse motives to do so exhibits patterns being largely consistent in a cross-cultural perspective, however, with differences in specific practices concerning gender, age, and formal education. A cluster analysis as well as taking a look at “influencers” provide a basis for developing differentiated strategies of brand communication and management respectively.
Poverty Reduction, Wealth Creation, and Tourism in Ethnic Minority Communities in Mainland Southeast Asia
Authors: Hipsher Scott
Published: March 2018

This article describes how there is a debate over the benefits and costs of international tourism and engagement with international trading networks for people living in areas where poverty continues to affect a large percentage of the population. An examination of the perspectives of ethnic minority micro-entrepreneurs on the impact of tourism on their lives and communities is presented. It was found most individuals from these communities find tourism increases livelihood opportunities and neither want to be isolated from the global economy nor want to abandon their traditional cultural values; instead it is preferred to have additional the additional livelihood options which tourism creates.
Time-Based Web Service Composition
Authors: Bey Fella , Bouyakoub Samia , Belkhir Abdelkader
Published: March 2018

This article describes how incorporating temporal constraints in web service composition results in more complex models and makes the verification of temporal consistency during the modeling and execution crucial. This article proposes a model named H-Service-Net based on the time petri net model to control and manage temporal consistency; the model also supports time constraints and exception handling. First, this approach proposes a modular approach for modeling composition using Extend Time Unit System, Allen's interval algebra, and comparison operators in a time petri net model to consider all types of temporal constraints. Subsequently, this article presents algorithms on checking temporal consistency and mechanism for exception handling and validating the system in an implementation tool (H-Service-Editor) based on the proposed approach that uses BizTalk Server 2013 to evaluate the implementation of temporal constraints and timeout exception handling. Finally, an exhaustive performance experiment is presented to assess the scalability of the authors' approach.
Handling Medical Emergencies Through Better Interaction With Real-World Entities via GSM
Authors: Yadav Sudhakar , Reddy B. Eswara , Srinivasa K.G.
Published: March 2018

This article aims to provide innovative system for tracking and monitoring health objects using RF transmitters and receivers. We begin by proposing a prototype for the system and perform a simulation to check the feasibility of this project before applying it to a real-world scenario. In this simulation model, we test the capability of the transmitter and receiver to communicate effectively and also display the data sent by the transmitter. As a result, highly flexible wireless controlled systems would enable the bridging of the distance between the user and the electronic device. This would provide an easier access to real world entities by just using mobile phones, without the need to be physically present near the object. Also, the addition ensures authenticated access to resources in view of security aspect. The workings of the system can be divided into two phases: phase one contains an RF transmitter and a receiver coupled with a central database; phase two contains a GSM modem with a unique SIM linked to the central data base via GSM network. In the first phase of the system, the RF transmitters are tagged to the objects of everyday use and have the capability to transmit signals and the paired receiver detects the transmission of the tagged object and stores its corresponding location in the central database. This is created specifically for information maintenance of the tagged objects, In the second phase of the system, a mobile phone is used to query the location of any tagged objects based on its availability in the vicinity, by sending a message to the SIM connected to a GSM modem. Object if present, the GSM modem fetches the location and other relevant information from the central database and encapsulates this information into a message which is sent back to the mobile device or phone that has requested the information.
M-Commerce Adoption in SMEs of China
Authors: Li Liwei , Wang Xiaohong
Published: March 2018

Based on the institutional theory, this article explores how institutional pressures motivate firms to adopt m-commerce, and how such effects are mediated by top management. Structural equation modeling with partial least square is used to analyze valid data from 204 small and medium-sized firms in China. The empirical results manifest as: mimetic pressures, coercive pressures, normative pressures which could directly affect a firm's intention to adopt m-commerce while coercive pressures and normative pressures have a positive effect on top management support. Top management support partly mediates the influence of two institutional pressures, coercive pressures and normative pressures, on the adoption intention of m-commerce. The final implications of the findings for research and practice are discussed.
Traumatic posterior fossa extradural hematoma: Experience at level I trauma center
Authors: Verma Satish , Borkar Sachin , Singh Pankaj , Tandon Vivek , Gurjar Hitesh , Sinha Sumit , Satyarthee Guru , Gupta Deepak , Agarwal Deepak , Sharma Bhawani
Published: March 2018

Introduction: Posterior fossa extradural hematoma (PFEDH) is rare among the traumatic brain injury and represent about 4–7% cases of all EDHs. This rare condition is rapidly fatal unless identified and intervened timely. Because of limited space in posterior fossa, comparatively small volume can cause clinical deterioration. Early diagnosis by cranial computed tomography and emergent evacuation is vital for a good outcome. Materials and Methods: This study was conducted at Level I trauma center at All India Institute of Medical Sciences, New Delhi, India. Hospital medical records were reviewed from September 2007 to June 2015. There were 856 cases of acute EDHs and of these 69 cases had PFEDHs. Records of patients with PFEDHs were reviewed for the mode of injury, Glasgow Coma Scale (GCS) at admission, imaging, type of intervention, outcome, and follow-up. GCS was assessed at 6 months and 12 months follow-up. Pertinent literature is reviewed. Results: Of these 69 patients, 51 were males and 18 females. The mean age of patients was 28.6 years (range 4–43 years). Forty-three patients had GCS 15 at admission, and only 4 of them had admission GCS <8. Mean EDH volume was 29.2 ml. Sixty-six patients were operated, three managed conservatively. Sixty-seven patients were discharged, of which, 56 (81.1%) had GCS 15. Two patients died. Most common associated injuries were long bone fractures (18, 26.1%) followed by blunt injury thorax (11, 15.9%). Mean follow-up duration was 69.2 months (range 6–94 months). At 6 months follow-up, 61 (88.4%) patients had good recovery (Glasgow Outcome Score [GOS] 5) and at 12 months, 62 (89.8%) had GOS 5. Conclusion: PFEDH are rare. They are usually associated with occipital bone fractures and may also have a supratentorial hematoma. It may be rapidly fatal due to the expansion of hematoma and compromise of the posterior cranial fossa space leading to brainstem compression, tonsillar herniation, and/or obstructive hydrocephalus. Early diagnosis and emergent evacuation lead to good outcome.
Neurosurgical interventions for occipital encephalocele
Authors: Rehman Lal , Farooq Ghulam , Bukhari Irum
Published: March 2018

Aims and Objectives: The aim of this study is to find the outcome of repair and resection of the occipital encephalocele. Study Design: Case series. Materials and Methods: The clinical data of fifty consecutive occipital encephalocele patients were retrieved from medical records including operative notes, postoperative follow-up visits, and postsurgical complications were noted for analysis from November 2009 to November 2013 at the Department of Neurosurgery, Jinnah Postgraduate Medical Centre, Karachi, Pakistan. All patients were assessed by computed tomography scan, magnetic resonance imaging brain, and ultrasound when needed. Physician's assessment, physical examination, and his/her questions to the family at follow-up were used as a tool to determine if there was a developmental delay rather than quantitative analysis like hydrocephalus questionnaires. Patients who developed complications and delayed milestone were regarded as no improvement and those who did not develop complications and achieved appropriate milestone were regarded as improved at 18 months follow-up. Results: Of 50 patients, 17 were males and 33 were females. The average age at presentation was 2.4 months. 16 (32%) patients had increased head circumference and hydrocephalus, 2 (4%) had associated Dandy–Walker cyst, 3 (6%) developed developmental delays, and 8 (15%) had a seizure disorder. None of our patients had neurological deficits. The size of the sac ranged from 2 cm × 3 cm to 27 cm × 15 cm. 9 (18%) patients were admitted with the complication of sac rupture and 2 (4%) patients sac ruptured after admission. Only one patient (2%) had a cerebrospinal fluid leak postoperatively that was repaired primarily without patch graft or dura seal while 4 (8%) developed hydrocephalus after repair of the sac which was treated with placement of ventriculoperitoneal shunt. One (2%) patient did not recover from anesthesia and expired. Conclusion: Encephalocele is commonly seen in the practice of neurosurgery in the world as well as in Pakistan. Modern neuroimaging, neurosurgical techniques, and neonatal neurological intensive care have greatly improved morbidity and mortality in the care of encephalocele.
A rare extra-axial midline tentorial adult medulloblastoma with dural-tail sign mimicking a meningioma
Authors: Doan Ninh , Patel Mohit , Nguyen Ha , Janich Karl , Montoure Andrew , Shabani Saman , Gelsomino Michael
Published: March 2018

Medulloblastomas are categorized as the World Health Organization Grade IV neoplasms. Only 33 cases have been reported of extra-axial, mostly in the cerebellar pontine angle and lateral cerebellar hemisphere, medulloblastomas in the current literature. Our study showcases the first case of an extremely rare presentation of an extra-axial midline tentorial adult medulloblastoma with the dural-tail sign mimicking a meningioma. To achieve the best possible outcome, a high index of suspicion for medulloblastoma is critical especially in young patient with an atypical posterior fossa mass as treatment regimens drastically different between a medulloblastoma and a meningioma.
Radiofrequency and methylprednisolone in treatment of lower back pain caused by facet joint syndrome: Comparison of the outcomes
Authors: Yasar Dagistan , Korgun Okmen , Emine Dagistan
Published: March 2018

Introduction: In this trial we have discussed the outcomes of radiofrequency ablation and methylprednisolone treatment in cases diagnosed with facet syndrome; and effects of treatment modality on quality of life is evaluated by visual analogue scale and Oswestry Disability Index. Materials and Methods: This prospective, study was conducted with 100 patients with diagnosis of facet joint syndrome. Patients, benefited from diagnostic block, were separated into two groups, with 50 cases in each. In Group 1, 40 mg of methylprednisolone acetate were injected into each level. In Group 2, radiofrequency needle was used to apply RF to the facet joint. Results: Demographic characteristics of patients were similar (P > 0.05). VAS values of the patients in Group 1 were significantly lower than the values prior to treatment (P < 0.05). Similarly, VAS values of the patients in Group 2 were also significantly lower than the values prior to treatment (P < 0.05). When VAS scores of the patients in Group 2 at 3rd and 6th months were compared with scores of the patients in Group 1, significant differences were also observed (P < 0.01).ODI results of the patients in Group 1 were significantly lower than the values prior to treatment (P < 0.05). Additionally ODI scores of the patients in Group 1 on 9th and 12th months are recorded as significantly lower. Conclusion: We consider that the steroid injection should be used as the first choice of treatment before the RF methods to be used in patients with back pain, caused by facet articulation pathology, if there are no contraindications.
Anatomical variability of the posterior communicating artery
Authors: Gunnal Sandhya , Farooqui Mujibuddin , Wabale Rajendra
Published: March 2018

Objective: Although posterior communicating artery (PCoA) is a smaller branch of the internal carotid artery, it gives the main contribution in the formation of circle of Willis (CW) by communicating with the internal carotid arterial system and the vertebro-basilar arterial system. The size of PCoA varies frequently. The present work aims to study the PCoA regarding its morphology, morphometry, and symmetry. Materials and Methods: This study was conducted on 170 human cadaveric brains. Brains were dissected carefully and delicately to expose all components of CW, especially PCoA. Morphological variations of PCoA were noted along with its morphometry and symmetry. Results: Morphological variations of PCoA were aplasia (3.52%), hypoplasia (25.29%), fenestration (0.58%), and persistent fetal pattern (16.47%). In the present study, we found the five different types of terminations of PCoA. Type I termination was the most common type, seen in 92.94% of cases, Type II termination was seen in 1.17%, Type III and Type IV terminations both were seen in 0.58%, and Type V was seen in 1.17%. The mean length of PCoA was 15.9 mm and 15.3 mm on the right and left sides, respectively. The mean diameter of PCoA was 2.1 mm and 1.9 mm on the right and left sides, respectively. Symmetry of PCoA was seen in 65.29% and asymmetric PCoA was seen in 34.70% of cases. Conclusion: The present study provides the complete description of PCoA regarding its morphology, symmetry, and morphometry. Awareness of these anatomical variations is important in neurovascular procedures.
Chalkstick fracture: A catastrophic injury
Authors: Tomar Suryapratap
Published: March 2018

Cervical spine region is known as very prone for injury because it is great mobility. Hyperflexion or hyperextension may create life-threatening injury to ankylosed cervical spine vertebra and spinal cord. The posttrauma result can range from neurological damage to the death. We present a case of a 52-year-old male patient, came to the emergency department with a history of road traffic accident induced quadriplegia and shock. The final diagnosis was chalkstick fracture of spine with complete cord transaction.
Language mapping in awake surgery: Report of two cases with review of language networks
Authors: Lim Liang , Idris Zamzuri , Reza Faruque , Wan Hassan Wan Mohd , Mukmin Laila , Abdullah Jafri
Published: March 2018

The role of language in communication plays a crucial role in human development and function. In patients who have a surgical lesion at the functional language areas, surgery should be intricately planned to avoid incurring further morbidity. This normally requires extensive functional and anatomical mappings of the brain to identify regions that are involved in language processing and production. In our case report, regions of the brain that are important for language functions were studied before surgery by employing (a) extraoperative methods such as functional magnetic resonance imaging, transmagnetic stimulation, and magnetoencephalography; (b) during the surgery by utilizing intraoperative awake surgical methods such as an intraoperative electrical stimulation; and (c) a two-stage surgery, in which electrical stimulation and first mapping are made thoroughly in the ward before second remapping during surgery. The extraoperative methods before surgery can guide the neurosurgeon to localize the functional language regions and tracts preoperatively. This will be confirmed using single-stage intraoperative electrical brain stimulation during surgery or a two-stage electrical brain stimulation before and during surgery. Here, we describe two cases in whom one has a superficial lesion and another a deep-seated lesion at language-related regions, in which language mapping was done to preserve its function. Additional review on the neuroanatomy of language regions, language network, and its impairment was also described.
Role of diffusion tensor imaging in brain tumor surgery
Authors: Dubey Amitesh , Kataria Rashim , Sinha Virendra
Published: March 2018

Object: The objective is to evaluate the role of diffusion tensor imaging (DTI) in intra-axial brain tumor cases (gliomas and metastasis). To preoperatively assess the integrity and location of white matter (WM) tracts and plan the surgical corridor to cause least damage to the WM tracts with minimum postoperative new neurological deficits. Materials and Methods: A total of 34 patients were included in this study. Pre-operative contrast-enhanced magnetic resonance imaging and DTI scans of the patients were taken into consideration. Pre- and post-operative neurological examinations were performed and the outcome was assessed. Results: Preoperative planning of surgical corridor and extent of resection were planned so that maximum possible resection could be achieved without disturbing the WM tracts. DTI indicated the involvement of fiber tracts. A total of 21 (61.7%) patients had a displacement of tracts only and they were not invaded by tumor. A total of 11 (32.3%) patients had an invasion of tracts by the tumor, whereas in 4 (11.7%) patients the tracts were disrupted. Postoperative neurologic examination revealed deterioration of motor power in 4 (11.7%) patients, deterioration of language function in 3 (8.82%) patients, and memory in one patient. Total resection was achieved in 11/18 (61.1%) patients who had displacement of fibers, whereas it was achieved in 5/16 (31.2%) patients when there was infiltration/disruption of tracts. Conclusion: DTI provides crucial information regarding the infiltration of the tract and their displaced course due to the tumor. This study indicates that it is a very important tool for the preoperative planning of surgery. The involvement of WM tracts is a strong predictor of the surgical outcome.
Hemispheric infarct following a cerebellar hematoma: A rare coincidence
Authors: Menon R , Kumar Vinod , Laskhman I , Nair Rajesh
Published: March 2018

Concomitant cerebral infarction developing soon after a parenchymal intracerebral hemorrhage is a rare occurrence. Usually, these remote site changes follow tumor decompression and are associated with hemorrhagic changes rather than infarcts. We report a case of a fatal malignant internal carotid territory infarct in a hospitalized patient being conservatively managed for a vermian hematoma and discuss the probable pathophysiology. Stroke physicians need to be aware that spontaneous intracerebral hematoma patients have a potential threat of developing large vessel occlusion with malignant cerebral infarcts, especially after surgical decompression. Although the exact pathogenesis is unknown, size of the clot, intraventricular hemorrhage, hydrocephalus, and aggressive reduction of blood pressure appear to be predictive factors.
Safe use of tissue plasminogen activator in conjunction with the integra camino bolt for the drainage of chronic subdural hematoma
Authors: Doan Ninh , Patel Mohit , Nguyen Ha , Doan Hayley , Montoure Andrew , Shabani Saman , Gelsomino Michael , Janich Karl
Published: March 2018

Chronic subdural hematoma (CSDH) is a relatively common condition encountered in a neurosurgical practice. There have been increased efforts in creating different treatment regimens for CSDH to improve patients' outcomes, including the addition of tissue plasminogen activator (tPA) in drains to reduce recurrences. Here, we present the first case report of the safe use of tPA in conjunction with an Integra Camino bolt for maximized drainage of CSDH with a successful neurological recovery and the complete resolution of the hematoma.
Ruptured distal anterior choroidal artery aneurysm presenting as isolated intraventricular hemorrhage: Case report and comprehensive review of the literature
Authors: Tan Chi , Lai Leon , Chandra Ronil
Published: March 2018

Distal anterior choroidal artery (AChA) aneurysms are infrequent. We discuss the case of a 59-year-old patient who presented with an isolated intraventricular hemorrhage (IVH) secondary to a ruptured distal AChA aneurysm. Initial noninvasive cerebral computed tomography angiography revealed no evidence of an underlying vascular pathology. The patient underwent further digital subtraction cerebral angiography, which revealed an aneurysm arising from the distal AChA segment. The aneurysm was successfully treated with surgical clip ligation. The current study highlights the importance of considering a ruptured distal AChA aneurysm as a potential source of isolated IVH.
Primary extradural meningioma of posterior fossa associated with acquired chiari malformation: A short review
Authors: Satyarthee Guru
Published: March 2018

Generally, meningioma is considered intracranial lesion occurring in the intradural compartment. However, meningioma can also occur and usually confined in the extradural compartment called as primary extradural meningioma (PEM). PEM represents a special subgroup of meningioma constitute about 1% of all meningioma. PEM arises outside the subdural compartment and usually contains neither connection underlying subdural structures nor extends into with subdural compartment. It is commonly located in the paranasal sinus, middle ear, rarely in the intradiploic spaces of calvarial bone such as temporal, frontal, and parietal bone and orbit but extremely uncommonly in the occipital and sphenoid bones. Authors did detailed Pubmed search for posterior fossa, occipital bone extradural, ectopic intraosseous meningioma which yielded only four publications in the form of isolated case report analyzing only five case of PEM. Authors report a rare case extradural meningioma in a 40-year-old male, who presented with progressive headache and gait imbalance. Magnetic resonance imaging study of brain revealed the presence of PEM of posterior fossa associated with acquired Chiari malformation. The patient was managed successfully surgically with excision of meningioma and release of associated acquired tonsiallar descent was carried out. Authors are analyzing total of five cases including four cases from published literature and one our current case. PEM of the posterior fossa tends to have equal predilection in male and female (3:3), with a mean age of 48 years (range 25–64 years). All cases were surgically and underwent gross total surgical excision. The clinical features, imagings, and management of this rare entity along with the pertinent literature are briefly discussed.
C1–C2 transverse foramen decompression by anterolateral approach as an alternative treatment in Bow Hunter's Syndrome
Authors: Cevik Serdar , Katar Salim , Hanımoǧlu Hakan
Published: March 2018

Bow hunter's syndrome (BHS) is characterized with repeating paroxysmal vertigo, nystagmus and ataxia caused by mechanical compression of the vertebral arteries. There is no definite diagnostic and treatment protocol. 26-year-old female patient admitted to the outpatient clinic with complaints of dizziness and seldom falls. Stenosis in the right vertebral artery at the level of C1 and C2 was discovered by the diagnostic modalities. In our patient, we first performed hemilaminectomy by posterior approach. But the symptoms of the patient did not recede, thus we performed decompression with the anterolateral approach by opening the foramens atlas and axis without disrupting the dynamics of the vertebrae and without the need for stabilization. The symptoms of the patient disappeared after this intervention. The patient had complete relief of symptoms at the first year follow up. Surgery must be planned to preserve the life quality of the patient and relieve complaints of the patients. To achieve these goals anterolateral approach must be tried before attempting posterior stabilization.
Intraoperative rupture cerebral aneurysm and computational flow dynamics
Authors: Senko Ilya , Shatokhin Anton , Bishnoi Ishu , Yamada Yasuhiro , Tanaka Riki , Suyama Daisuke , Kawase Tukasa , Kato Yoko
Published: March 2018

Intraoperative aneurysmal rupture (IAR) is the most fearsome complication of aneurysm surgery. IAR associates with high morbidity and mortality. In recent years, we have many studies regarding using computational fluid dynamics (CFD) in aneurysm surgery. CFD helps in calculating the velocity of blood flowing in the aneurysm sac, the pressure in the aneurysm sac, and wall shear stress (WSS). CFD also helps in predicting nature of aneurysm wall and thus may warn about different intraoperative microscopy findings in aneurysms. Using its application, surgeon may become more careful in doing microsurgical sharp dissection. A 40-year-old female admitted with diagnosis of unruptured anterior communicating artery aneurysm. CFD analysis demonstrated high intra-aneurysmal pressure and divergent WSS in dome. During sharp dissection, there was intraoperative rupture aneurysm twice which was managed with cotton tamponade and glue and temporary clipping aneurysm. Indocyanine green video angiography showed working parent arteries and nonfunctioning aneurysm. After operation, the patient recovered fully and had a modified Rankin score of 1. This case demonstrated importance of preoperative planning of aneurysm surgery using CFD analysis. IAR is associated with an increased risk for an unfavorable outcome. Accurate preoperative planning with studying flow dynamics and structure of aneurysm may help in use sharp microsurgical dissection more cautiously.
Многообразия над конечными полями: количественная теория
Authors: Vladut Sergei Georgievich , Nogin Dmitrii Yur'evich , Tsfasman Michael Anatol'evich
Published: March 2018

Мы рассматриваем алгебраические многообразия над конечными полями с точки зрения таких их инвариантов, как число точек многообразия, определенных над основным полем и его расширениями. Случай кривых активно исследовался в течение последних тридцати пяти лет, и ему посвящены сотни работ. В размерности два и выше ситуация становится гораздо более сложной и малоизученной. В данном обзоре мы приводим основные подходы к проблеме и описываем существенную часть имеющихся результатов в этом направлении.
Библиография: 102 названия.
Топологическая теорема Тверберга: доказательства и контрпримеры
Authors: Shlosman Semen Bensionovich
Published: March 2018

В статье кратко описывается история топологической теоремы Тверберга (TTT) и напоминаются основные конструкции и их свойства. В частности, детально описывается клеточная структура пространства $K(S_r,1)$, где $S_r$ - группа перестановок.
Библиография: 9 названий.
Разности идемпотентов в $C^*$-алгебрах и квантовый эффект Холла
Authors: Bikchentaev Airat Midkhatovich
Published: March 2018

Пусть $\varphi$ - след на унитальной $C^*$-алгебре $\mathcal{A}$, $ \mathfrak{M}_{\varphi}$ - идеал определения следа $\varphi$. Получен $C^*$-аналог квантового эффекта Холла: если $P, Q \in \mathcal{A}$ - идемпотенты и $P-Q \in \mathfrak{M}_{\varphi}$, то $\varphi((P-Q)^{2n+1})=\varphi (P-Q)\in \mathbb{R}$ для всех $n\in\mathbb{N}$. Пусть изометрия $U\in \mathcal{A}$ и $A=A^*\in \mathcal{A}$ такие, что $I+A$ обратим и $U-A\in \mathfrak{M}_{\varphi}$ с $\varphi (U-A)\in \mathbb{R}$. Тогда $I-A, I-U\in \mathfrak{M}_{\varphi}$ и $\varphi (I-U)\in \mathbb{R}$. Пусть $n \in \mathbb{N}$ и $\dim \mathcal{H}=2n+1$, операторы симметрии $U,V \in \mathcal{B}(\mathcal{H})$ и $W=U-V$. Тогда оператор $W$ не является симметрией и, если $V=V^*$, оператор $W$ не унитарен.
Интегрируемые семиточечные дискретные уравнения и эволюционные цепочки второго порядка
Authors: Adler Vsevolod Eduardovich
Published: March 2018

Рассмотрены дифференциально-разностные уравнения, определяющие непрерывные симметрии дискретных уравнений на треугольной решетке. Показано, что определенная комбинация непрерывных потоков может быть представлена как скалярная эволюционная цепочка второго порядка. Общая конструкция иллюстрируется рядом примеров, включая аналог эллиптической цепочки Ямилова.
Обратная задача рассеяния для уравнения Шредингера с дополнительным квадратичным потенциалом на всей оси
Authors: Guseinov Idayat Magomed ogly , Khanmamedov Agil Khanmamed ogly , Mamedova Afag Faik
Published: March 2018

Рассмотрено уравнение Шредингера с дополнительным квадратичным потенциалом на всей оси. Методом операторов преобразования изучены прямая и обратная задачи теории рассеяния. Получены основные интегральные уравнения обратной задачи. Доказана однозначная разрешимость основных уравнений.
Detection of Immunoglobulin G Antibodies to Taenia solium Cysticercosis Antigen Glutathione-S-Transferase–rT24H in Malian Children Using Multiplex Bead Assay
Authors: Moss Delynn M. , Handali Sukwan , Chard Anna N. , Trinies Victoria , Bullard Stevan , Wiegand Ryan E. , Doumbia Seydou , Freeman Matthew C. , Lammie Patrick J.
Published: March 2018

Blood samples from 805 students attending 42 elementary schools in Mopti, Sikasso, and Koulikoro regions, and Bamako district in Mali participated in a school water, sanitation, and hygiene intervention. Immunoglobulin (Ig) G responses to several antigens/pathogens were assessed by a multiplex bead assay (MBA), and the recombinant Taenia solium T24H antigen was included. Of all students tested, 8.0% were positive to rT24H, but in some schools 25–30%. A cluster of 12 widespread school locations showed not only a relative risk of 3.23 for T. solium exposure and significantly higher IgG responses (P < 0.001) but also significantly lower elevation (P = 0.04) (m, above sea level) compared with schools outside the cluster. All schools at elevations < 425 m showed significantly higher IgG responses (P = 0.017) than schools at elevations ≥ 425 m. The MBA is an excellent serological platform that provides cost-effective opportunities to expand testing in serosurveys.
Leptomeningeal Carcinomatosis: Easy to Miss
Authors: Sekhar A , Corbo B , Das K , Biswas S
Published: March 2018

Leptomeningeal carcinomatosis is a devastating condition with very poor prognosis. With advances in cancer treatment leading to improved survival in solid tumours, the incidence of ante-mortem diagnosis of leptomeningeal carcinomatosis is likely to rise. Without a high index of suspicion and appropriate imaging the diagnosis can be missed. We report two cases of leptomeningeal carcinomatosis secondary to metastatic breast disease with varied clinical presentation where the diagnosis was initially missed.
Checklist of alien plant species in a natural protected area: Anaga Rural Park (Tenerife, Canary Islands); effect of human infrastructures on their abundance
Authors: Expósito Ana B. , Siverio Antonio , Bermejo Luis A. , Sobrino-Vesperinas Eduardo
Published: March 2018

Background and aims – Invasive alien (exotic) species are one of the most serious threats to the conservation of biodiversity on the planet. This is especially true on islands, given the fragility of their ecosystems and high levels of endemicity in both species and ecosystems. The problem is particularly acute in the Canary Islands, a biodiversity `hot spot´, where there is widespread high endemicity and unique biodiversity. This paper presents the first comprehensive inventory of alien plant species in Anaga Rural Park (ARP) (Tenerife, Canary Islands, Spain) a Natural Protected Area, currently proposed as a UNESCO Biosphere Reserve. Anaga is also outstanding for including a relict Tertiary era laurel-forest ecosystem that hosts a large number of palaeoendemics.Methods – Surveys were conducted along itineraries through the different ecosystems of ARP to determine the alien plant species in areas with different levels of human impact.Key results – Two hundred and sixteen alien species were identified, belonging to 53 families and 141 genera, especially concentrated in the most anthropic areas, noting the possibly competitive coexistence of aliens and local endemics of importance in the ecosystem. This is the first overall comprehensive study on the importance of alien species in ARP. Surveys confirmed how human infrastructure and activities significantly favour the presence and diversity of exotic species. Using multivariate statistical analysis, significant differences were found between the species diversity of alien flora and the proximity of anthropic areas. The presence of Cuscuta campestris Yunck was detected, being a second record for the Canaries and the first for ARP.Conclusions – A large number of alien plant species inhabit ARP, affecting all its ecosystems. This is largely the result of the human activities within it, and poses a risk to its conservation and the survival of numerous endemic taxa s. str.
Atmospheric characterization through fused mobile airborne and surface in situ surveys: methane emissions quantification from a producing oil field
Authors: Leifer Ira , Melton Christopher , Fischer Marc L. , Fladeland Matthew , Frash Jason , Gore Warren , Iraci Laura T. , Marrero Josette E. , Ryoo Ju-Mee , Tanaka Tomoaki , Yates Emma L.
Published: March 2018

Abstract. Methane (CH4) inventory uncertainties are large, requiring robust emission derivation approaches. We report on a fused airborne–surface data collection approach to derive emissions from an active oil field near Bakersfield, central California. The approach characterizes the atmosphere from the surface to above the planetary boundary layer (PBL) and combines downwind trace gas concentration anomaly (plume) above background with normal winds to derive flux. This approach does not require a well-mixed PBL; allows explicit, data-based, uncertainty evaluation; and was applied to complex topography and wind flows. In situ airborne (collected by AJAX – the Alpha Jet Atmospheric eXperiment) and mobile surface (collected by AMOG – the AutoMObile trace Gas – Surveyor) data were collected on 19 August 2015 to assess source strength. Data included an AMOG and AJAX intercomparison transect profiling from the San Joaquin Valley (SJV) floor into the Sierra Nevada (0.1–2.2 km altitude), validating a novel surface approach for atmospheric profiling by leveraging topography. The profile intercomparison found good agreement in multiple parameters for the overlapping altitude range from 500 to 1500 m for the upper 5 % of surface winds, which accounts for wind-impeding structures, i.e., terrain, trees, buildings, etc. Annualized emissions from the active oil fields were 31.3 ± 16 Gg methane and 2.4 ± 1.2 Tg carbon dioxide. Data showed the PBL was not well mixed at distances of 10–20 km downwind, highlighting the importance of the experimental design.
Assessing the degree of plug flow in oxidation flow reactors (OFRs): a study on a potential aerosol mass (PAM) reactor
Authors: Mitroo Dhruv , Sun Yujian , Combest Daniel P. , Kumar Purushottam , Williams Brent J.
Published: March 2018

Abstract. Oxidation flow reactors (OFRs) have been developed to achieve high degrees of oxidant exposures over relatively short space times (defined as the ratio of reactor volume to the volumetric flow rate). While, due to their increased use, attention has been paid to their ability to replicate realistic tropospheric reactions by modeling the chemistry inside the reactor, there is a desire to customize flow patterns. This work demonstrates the importance of decoupling tracer signal of the reactor from that of the tubing when experimentally obtaining these flow patterns. We modeled the residence time distributions (RTDs) inside the Washington University Potential Aerosol Mass (WU-PAM) reactor, an OFR, for a simple set of configurations by applying the tank-in-series (TIS) model, a one-parameter model, to a deconvolution algorithm. The value of the parameter, N, is close to unity for every case except one having the highest space time. Combined, the results suggest that volumetric flow rate affects mixing patterns more than use of our internals. We selected results from the simplest case, at 78 s space time with one inlet and one outlet, absent of baffles and spargers, and compared the experimental F curve to that of a computational fluid dynamics (CFD) simulation. The F curves, which represent the cumulative time spent in the reactor by flowing material, match reasonably well. We value that the use of a small aspect ratio reactor such as the WU-PAM reduces wall interactions; however sudden apertures introduce disturbances in the flow, and suggest applying the methodology of tracer testing described in this work to investigate RTDs in OFRs to observe the effect of modified inlets, outlets and use of internals prior to application (e.g., field deployment vs. laboratory study).
Retrieval of snowflake microphysical properties from multi-frequency radar observations
Authors: Leinonen Jussi , Lebsock Matthew D. , Tanelli Simone , Sy Ousmane O. , Dolan Brenda , Chase Randy J. , Finlon Joseph A. , von Lerber Annakaisa , Moisseev Dmitri
Published: March 2018

Abstract. We have developed an algorithm that retrieves the microphysical properties of falling snow from multi-frequency radar observations. This work builds on previous studies that have indicated that three-frequency radars can provide information on snow density, potentially improving the accuracy of snow parameter estimates. The algorithm is based on a Bayesian framework, using lookup tables mapping the measurement space to the state space, which allows fast and robust retrieval. In the forward model, we calculate the radar reflectivities using recently published snow scattering databases. We demonstrate the algorithm using multi-frequency airborne radar observations from the OLYMPEX/RADEX field campaign, comparing the retrieval results to hydrometeor identification using ground-based polarimetric radar, and also to collocated in situ observations made using another aircraft. Using these data, we examine how the availability of multiple frequencies affects the retrieval accuracy, and test the sensitivity of the algorithm to the prior assumptions. The results suggest that multi-frequency radars are substantially better than single-frequency radars at retrieving snow microphysical properties. Meanwhile, triple-frequency radars can retrieve wider ranges of snow density than dual-frequency radars, and better locate regions of high-density snow such as graupel, although these benefits are relatively modest compared to the difference in retrieval performance between dual- and single-frequency radars.
University student social media use and its influence on offline engagement in higher educational communities
Authors: Sutherland Karen , Davis Cindy , Terton Uwe , Visser Irene
Published: March 2018

Previous research has emphasised social media adoption by students and the implementation of social media by educators, yet few studies have explored whether students are using it to facilitate engagement in offline environments with peers within university communities. Studies suggest engagement in educational communities and extra-curricular activities can reduce student attrition. This study surveyed 106 undergraduate students to investigate whether students using social media to interact online with their university felt: (i) connected to the broader university community, and (ii) social media helped them engage offline by meeting up with peers and attending university events. The results indicated that the majority (82%) never or rarely used the technology to facilitate offline engagement within their academic communities. Fourth year students were most likely to use social media to engage offline (66.7%). However, more than half of students (52.8%) felt that university social media profiles helped them to feel part of their academic community.
Connecting embedded and stand-alone peer mentoring models to enhance student engagement
Authors: Cooper Rhys
Published: March 2018

This paper outlines the Trident Student Mentoring Program that runs in the College of Engineering at Victoria University, Melbourne, Australia. The program offers both embedded and stand-alone models of peer mentoring services to the same cohort of first-year students. It shows that by forming strong links between these two types of peer mentoring models, the inherent challenges of both, such as low attendance rates in stand-alone models and short periods of peer to peer time in embedded models, are mitigated.
Teaching Shakespeare through blended learning
Authors: Hawkes Lesley , Thomas Glen
Published: March 2018

This paper describes and discusses experimentation with the use of blended learning in teaching Shakespeare. Previous iterations of the subject in a traditional lecture and tutorial format had seen a decline in student attendance and a fall in student achievement at the higher grade levels. A further complicating issue was the range of expectations from the cohort, which comprised students from Creative Writing, Drama, and Education, a factor which also highlights the cross-disciplinary nature of teaching Shakespeare. A blended learning and lectorial format was employed to facilitate small group discussion of the plays in conjunction with a wider social and historical overview. Student feedback indicated that the changes to the delivery method were received positively, although some questions do remain concerning levels of student engagement and the specific disciplinary needs of student cohorts. The findings of the teaching of this subject will translate usefully to other fields and disciplines, especially as more and more subjects take up blended learning. The findings indicate that it is not enough to take up new technologies in the teaching of a unit. The learning environment must also be rethought and reconceptualised.
First year students’ perceptions of academic literacies preparedness and embedded diagnostic assessment
Authors: Palmer Lorinda , Levett-Jones Tracy , Smith Rosalind
Published: March 2018

This paper reports findings from the second stage of a mixed-methods study of embedded academic literacies and diagnostic assessment—specifically first-year nursing students’ perceptions of the MASUS procedure. We found overwhelming support from participants (85%) in favour of embedded diagnostic assessment. The main reasons for this were receiving constructive, individualised feedback and insights into expectations and requirements. This was important as over a quarter of participants said they had “no idea” about the academic literacy requirements of university when they commenced their program and 60% had not formally studied for at least seven years. Those without recent study experience or with prior poor academic performance expressed high levels of anxiety about academic literacy requirements and lacked confidence in their writing abilities. These findings indicate how stressful the process of mastering academic literacies is for many first-year students’ and highlight the potential benefits of embedding for retention and engagement.
Site Characteristics, Historical Market Conditions, and Spatial Changes in Pennsylvania Tobacco Production
Authors: Latzko David
Published: March 2018

This article deals with the physical characteristics of the sites selected for the production of tobacco in Pennsylvania, nature of tobacco growing, the response of tobacco farmers to changing market conditions, and the spatial distribution of tobacco production within Pennsylvania since 1840. Factors underlying the establishment and persistence of tobacco production in south-central Pennsylvania include soil and climate constraints, cultural conditions, and economic opportunities. Yet, there were periods when market conditions expanded the tobacco-growing region in Pennsylvania. In the late nineteenth century, tobacco was widely grown across Pennsylvania. After the turn of the last century, decreases in the demand for cigar tobacco led to a contraction of the state's tobacco growing region while the elimination in 2004 of tobacco production quotas established during the Great Depression resulted in an expansion of output outside of Lancaster County and a change in the varieties of tobacco grown in Pennsylvania.
Protest and Participation: Reconsidering the Quaker Slave Trade in Early Eighteenth-Century Philadelphia
Authors: Daniels Jason
Published: March 2018

This article reconsiders the complex relationship between Quakers and African slavery during the early eighteenth century by examining a small contingent of Quaker merchants who directed the intercolonial African slave trade in Philadelphia. This is much more than an aberrant moment in the larger story of Quaker antislavery. The first two decades of the eighteenth century, when Quakers were the colony's largest slave owners and most active in the slave trade, witnessed the coalescence of a declining economic interest in the intercolonial slave trade and the emergence of an embryotic conversation about the morality of African slavery. Rather than focusing on the moral and religious critique of slavery, this article instead reorients our focus to the crucial role that practical considerations and economic motivations played in the evolution of antislavery among the Society of Friends.
The Impact of Internally Generated Revenue on Economic Development in Nigeria
Authors: Omodero Cordelia Onyinyechi , Ekwe Michael Chidiebere , Ihendinihu John Uzoma
Published: March 2018

The study investigated the impact of internally generated revenue (IGR) on economic development of Nigeria. The inability of States and Local governments in Nigeria to generate enough revenue to cope with their expenditure responsibilities has been a serious challenge. The improper use of IGR and corruption have remained a setback to economic development in Nigeria, hence the clamour from the citizens. This study made use of ex-post facto research design to specifically examine the impact of total IGR (TIGR), Federal Government Independent Revenue (FGIR), States IGR (SIGR) and Local IGR (LIGR) Governments IGR on the Real Gross Domestic Product (RGDP i.e. proxy for economic development) of the country. The time series data employed covered a period from 1981 to 2016 and were gathered from the Central Bank of Nigeria (CBN) Statistical Bulletin. The statistical tool used for the data analysis was the multi-regression and t-test for test of hypotheses. The findings of the study revealed that TIGR, SIGR and LIGR have robust and significant positive impact (p-value = 0.000 < 0.05) on RGDP, while FGIR also indicated positive and significant influence on RGDP. There was an existence of high correlation between the dependent and independent variables. The study concluded that the positive impact of IGR is not out of place but the physical evidence is apparently lacking and therefore government policies that could eradicate sharp practices in the government system are required. The study also recommends that government official with corruption history should not be allowed to continue to handle responsibilities rather; people with outstanding integrity should be given opportunity to occupy government positions that are sensitive and could help achieve economic development objectives.