bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of Stormwater Biofilter Media for Escherichia coli Removal in a Laboratory Microcosm
Authors: Kleinheinz Gregory T. , Zehms Tabitha , Koenig Kathryn
Published: October 2017

Recreational water sites such as beaches along lakes, rivers, or oceans, are one of the most popular activities in many parts of the world. Recently rainfall and runoff due to rainfall events has been associated with increasing microbial levels in recreational water. This runoff can lead to beach closures and potentially unsanitary conditions at popular swimming beaches. The impact of stormwater on beach water quality has led to a myriad of option for controlling stormwater. Some of these include grass buffer partitions, stormwater detention basins, media filters, catch basin inserts, and infiltration units. Biofilters, or infiltration units are gaining popularity as a treatment option for stormwater around the Great Lakes basin, but we are aware of no studies that have looked at the indicator organism (i.e. Escherichia coli, or E.coli) removal potential of these infiltration units and the media used in them. The overall objective of this study was to evaluate the performance of a stormwater biofilter medium in removing the indicator organism E.coli in a laboratory system. When several laboratory biofilter system were challenged with E.coli concentrations of 2.82E3 and 2.85E5 E.coli/100mL of simulated stormwater in a 1.25 cm rain event, the systems were able to remove between 83 and 100% of the E.coli in this influent. During a subsequent 1.25 cm rain event with E.coli-free water, the biofilter was able to retain 68%-100% of the E.coli originally inoculated into the system. The results of this study indicate that these systems hold promise for mitigation of E.coli from storm water near recreational beaches. These findings will assist beach managers, engineers, and municipal stake holders evaluate the usefulness of biofilter infiltration as a storm water management tool in order to decrease E.coli input into beach areas.
Biological Responses to New Advanced Surface Modifications of Endosseous Medical Implants
Authors: Singhatanadgit Weerachai
Published: October 2017

Implantable medical devices are increasingly important in the practice of modern medicine. However, patients with severely poor bone quality and quantity require highest implant osseointegration for the long-term success. A number of newly-developed advanced surface modifications of medical implants have recently been introduced to the medical implant system. Understanding the mechanisms by which osteogenic cells respond to such materials is therefore of major importance in developing the most effective materials to promote functional osseointegration. Diverse studies using materials with a wide range of new surface modification techniques have demonstrated the pivotal role of surface treatments in cell adhesion, proliferation and lineage specific differentiation. These events underlie the tissue responses required for bone healing following implant placement, with the interaction between adsorbed proteins on the implant surface and surrounding cells eliciting body responses to the treated implant surface. This review illustrates tissue responses to the implant material following implant placement and highlights cellular responses to new advanced implant surface modifications. Such information is of utmost importance to further develop several new advanced surface modifications to be used in the new era medical implantable devices.
Properties of Hydroxyapatite from Bovine Teeth
Authors: Elkayar Aida , Elshazly Yehia , Assaad Mariana
Published: October 2017

The objective of this work was to study the production of hydroxyapatite (HA) from bovine teeth. Hydroxyapatite (HA) was produced from bovine teeth powder after calcination at 1150 °C. It was discovered that the sample preparation process influences its properties, so, crystal structure and thermal stability of HA were investigated. The X-Ray diffraction analysis (XRD) results confirmed that HA has been successfully produced. Fourier transform infrared spectroscopic (FT-IR) study confirmed the presence of hydroxyl (OH) and phosphate (PO4−3) functional groups. The scanning electronic microscope (SEM) was employed to identify the surface morphology of HA, and showed the nanoporous structure throughout the matrix. The sample constituents such as Ca, P, K … etc., and their values were determined by Energy dispersive X-Ray (EDX).
Barriers to Healthcare in a Multiethnic Cohort of Systemic Lupus Erythematosus (SLE) Patients: Patient and Physician Perceptions
Authors:   CaNIOS Investigators, Law Genevieve , Pope Janet , Lalani Sheliza , Silverman Earl , Cooper Glinda , Fortin Paul , Zummer Michel , Smith C. Douglas , Petty Ross , Tucker Lori , Albert Lori , Huber Adam , Ramsey Susanne , Arbillaga Hector , Chedéville Gaëlle , Hudson Marie , Peschken Christine
Published: October 2017

Objective

Barriers to medical care may influence health status. It is unclear whether problems with access can predict clinical outcomes in lupus. This study aimed to determine whether care barriers are associated with increased disease activity and damage in a multi-center, multiethnic SLE cohort. We also compared concordance between care barriers as reported by the patient and lupus specialist.

Methods

Data from SLE patients in 12 Canadian centers collected at annual visits, including demographics, treatment, disease activity and damage were analyzed.

Results

654 patients were enrolled with ethnic groups being Caucasian [CC] (64%), Aboriginal [ABO] (9%), Asian [AS] (21%), and Black [BLK] (6%). 50.8% had at least one barrier to care including travel to a rheumatologist (32.0%), waiting to see a rheumatologist and cost of medications. Access to medication and costs were significantly associated with co-morbidity (p < 0.001, p = 0.04). There were significant associations between ethnicity and any physician perceived care barrier < p < 0.001), mostly in Aboriginal. Doctors identified half of patients who had access to medication problems (p = 0.003) and the relationship between doctors and patients identifying similar care barriers was weak (r = 0.09). A lower total household income significantly predicted the presence of any care barrier (p < 0.001).

Conclusions

Despite access to a lupus specialist many care barriers were identified, although we found few associations between care barriers and patient outcomes. The cost of medication was related to SLE disease activity; however, we cannot determine if this was cause or effect. Care barriers identified by lupus patients are significantly underestimated by physicians.
Hypertrophic Synovitis of the Facet Joint Causing Root Pain
Authors: Iwatsuki Koichi , Yoshimine Toshiki , Aoki Masanori , Yoshimura Kazuhiro
Published: October 2017

Osteoarthritic changes in the facet joints are common in the presence of degenerative disc disease. Changes in the joint capsule accompany changes in the articular surfaces. Intraspinal synovial cysts that cause radicular pain, cauda equina syndrome, and myelopathy have been reported; however, there have been few reports in orthopedic or neurosurgical literature regarding hypertrophic synovitis of the facet joint presenting as an incidental para-articular mass. Here, we report a case of hypertrophic synovitis causing root pain. We describe the case of a 65-year-old man suffering from right sciatica and right leg pain in the L5 nerve-root dermatome for 1 year; magnetic resonance imaging (MRI) revealed an enhanced mass around the L4–5 facet joint. We investigated this mass pathologically. After right medial facetectomy, the symptoms resolved. Pathological investigation revealed this mass was hypertrophic synovitis. Hypertrophic synovitis of the facet joint might cause root pain.
A Comprehensive Clinicopathologic Analysis Suggests that Vascular Endothelial Growth Factor (VEGF) is the Most Likely Mediator of Periosteal New Bone Formation (PNBF) Associated with Diverse Etiologies
Authors: Lakey Meredith A. , Klein Michael J. , Faye-Petersen Ona M.
Published: October 2017

Periosteal new bone formation (PNBF) is the means by which appositional bone growth normally takes place on the surfaces of compact bone. Alterations in the periosteal microenvironment trigger complex interactions between osteoblasts and endothelial cells to promote PNBF. Physiologic processes like mechanical stress result in normal PNBF; but, a variety of pathologic processes result in excessive PNBF. The production of sufficient bone to be detectable by conventional radiography is a common feature of diverse etiologies, including infection; inflammation; prostaglandin E2 administration for ductal-dependent congenital heart disease; metabolic and hormonal abnormalities; neoplasms; fracture repair; systemic hypoxia; and hypertrophic osteoarthropathy. While the clinical settings and distribution of affected bone sites in these conditions are different, the histopathology of the PNBF is essentially identical; so, it seems logical that a common pathway might mediate them all. By combining the observations and insights gained from osseous research and studying the clinical pathology of these diverse conditions, we constructed a comprehensive pathway to explain PNBF. In doing so, it seems likely that Vascular Endothelial Growth Factor (VEGF) is the most likely common mediator of the pathways that lead to PNBF.
Relationship between Synovial Fluid Inflammatory Cells and Grade of Inflammation of Synovium in Patients with Spondylarthropathy
Authors: Luukkainen Reijo , Söderström Karl-Ove , Möttönen Milja , Luukkainen Pekka
Published: October 2017

Objective

To study whether the analysis of synovial fluid (SF) inflammatory cells can be used for the estimation of the grade of inflammation in the synovium and, therefore, for the prediction of the possible development of joint destruction in spondylarthropathy.

Methods

Forty-one patients with spondylarthropathy and hydropsy in a knee joint were studied. The cellular composition of SF aspirates was investigated and the grade of inflammation in synovial biopsy samples was evaluated by analyzing histological needle biopsy specimens.

Results

The count of SF polymorphonuclear leukocytes (PMN) reflected significantly the activity of acute inflammation. None of the SF cells reflected the chronic inflammation in the synovium.

Conclusion

The number of SF PMNs may reflect the severity of acute inflammatory process in the synovium in patients with spodylarthropathy at a given moment, but the analysis of SF aspirates may not be of use in estimating the activity of chronic phase of inflammation presumably causing the joint destruction.
Comparison of Antigenic Regions Identified on IgG1Fc Using Bioinformatics vs Pepscan Analysis
Authors: Nelson Paul N. , Westwood Olwyn M.R. , Freimanis Graham , Roden Denise , Sissaoui Samir , Rylance Paul , Hay Frank C.
Published: October 2017

Epitope mapping allowed the location of antigenic determinants on a protein macromolecule to be identified. In particular, pepscan techniques that utilize a series of overlapping peptides, help detect key amino acid residues that are important in antibody recognition and binding. In a previous study, we employed 15-mer peptides spanning the entire length of IgG1Fc to ascertain successfully the target epitopes of isotypic/allotypic monoclonal reagents.

As an extension to this work we have used these peptides to evaluate the location of epitope targets of five IgM rheumatoid factor antibodies (RFAbs). Overall, 2 antibodies, RFAb TS2 and TS1, detected a similar epitope within the CH3 domain (360-KNQVSLTCLVKGFYP-374), whilst 1 (RFAb SJ1) recognised an epitope in the CH2 domain (294-EQYNSTYRVVSVLTV-308). In contrast, 2 RFAbs, PRSJ2 and PRTS1 detected four and five epitopes respectively within the Fc region. RFAb PRSJ2 recognised epitopes detected by RFAB TS2 and TS1 but also further epitopes in the CH2 domain (256-TPEVTCVVVDVSHED-270) and CH3 domain (418-QQGNVFSCSVMHEAL-432). Similarly, RFAb PRTS1 detected all four epitopes plus a fifth in the CH3 domain (382-ESNGQPENNYKTTPP-396). In essence there was a consensus of target epitopes identified by these rheumatoid factor antibodies. Interestingly, two epitopes (256–270, CH2 domain and 360–374, CH3 domain) were novel in that they had not been identified in previous pepscan studies. The other epitopes recognised, either overlapped or were immediately adjacent to previous epitopes detected by poly/monoclonal rheumatoid factor antibodies.

Molecular modelling (PCImdad) of IgG1Fc showed that all five epitopes were exposed and surface accessible for antibody interaction. In addition, a bioinformatics analysis of the Fc region using ExPASy was employed to identify key antigenic determinants. This ‘in silico’ approach may provide a means of determining key regions without the need to develop overlapping peptides spanning the entire length of a macromolecule.
Birth MCV and MCH are Quite Reliable Parameters for the Prediction of Alpha Thalassemia Trait
Authors: Akram Al-Hilali , Khalida Abu Saud , Sawsan Sofi , Charles La Cock
Published: October 2017

To assess some simple blood parameters at birth that can be used as a basis to suspect α-thalassemia minor (ATM), a prospective study involving 202 consecutive neonates with MCV of less than 95 fl or less were checked for Hb Barts by HPLC. The group was divided into two, one with an MCV of 90-95 (89 cases) and the other with an MCV below 90 (113 cases). For control, 104 consecutive neonates with an MCV ≥ 95 fl were similarly checked. It has been confirmed that an MCV that is below 90 fl, especially with and MCH of ≤30 pg is a strong indicator of the presence of ATM (109/113). On the other hand, MCV of 90 or more, especially with an MCH of 30 or more is a strong negative indicator for ATM (70/89). Firm diagnosis of ATM at birth can thus be secured in majority of neonates.
Castleman's Disease: A Study of a Rare Lymphoproliferative Disorder in a University Hospital
Authors: Abdul-Rahman Ibrahiem Saeed , Al-Amri Ali M. , Ghallab Khalid Qassim
Published: October 2017

Castleman's disease (CD) is a group of rare lymphoproliferative disorders sharing characteristic clinical and histological features, and usually accompanied by a marked systemic inflammatory response. Three histological patterns of lymph nodes were described: the hyaline-vascular, the plasma-cell and the mixed types. The former is more common (80%-90%) and tends to be localized. The plasma cell type is more aggressive and usually multicentric. It is interesting that the inflammatory manifestations seem to be related to a lymph node lesion, because the systemic symptoms and inflammatory activity can return to normal after surgical excision or successful medical treatment of the disease.

We report here our 15-year experience with this rare disease in King Fahd Hospital of the University, Al-Khobar, Saudi Arabia, focusing on the clinical features, therapy, and patients'outcome.
Quantification of Drug-Induced mRNA in Human Whole Blood ex vivo
Authors: Mitsuhashi Masato , Endo Katsuya , Obara Kazuhiko , Izutsu Hiroshi , Ishida Taishi , Chikatsu Norio , Shinagawa Atsushi
Published: October 2017

Apoptosis was induced in heparinized human whole blood by 3 different ways (radiation, bleomycin, or etoposide), and various mRNA were quantified using the method we reported (Clin. Chem. 2006; 52:634-642). We found that cyclin-dependent kinase inhibitor 1A (p21) and p53 upregulated modulator of apoptosis (PUMA) were the most sensitive and universal mRNA markers of apoptosis in leukocytes. In order to define positive and negative responses, a synthetic RNA was spiked into the lysis buffer and the fold increase was calculated. As a result, 837/880 (95.1%) of data points stayed between 0.75 and 1.5 fold increase, and 874/880 (99.3%) were within 0.5-2.0 fold increase. When blood samples from 40 healthy adults were stimulated with 22 different drugs, more than 75% of the samples responded to bleomycin (1 μM), idarubicin (2 μM), vincristine (1 μM), daunorubicin (2 μM), cytarabine (10 μM), to induce p21 and/or PUMA mRNA, and approximately 25% showed no induction. Significant correlation was found between p21 and PUMA mRNA responses, and between daunorubicin and cytarabine, idarubicin, and vincristine for both p21 and PUMA. The quantification of drug-induced mRNA in whole blood will be considered as ex vivo, and is a suitable platform for biomarker screening as well as a model system for drug sensitivity tests in future.
A Disease Mechanism Underlying Bleeding in Wiskott-Aldrich Syndrome
Authors: Tsuboi Shigeru
Published: October 2017

The Wiskott-Aldrich Syndrome (WAS) is an × chromosome-linked immunodeficiency disorder. The most common symptom in WAS is bleeding. Several clinical investigations indicate that low platelet counts and defective platelet aggregation are the major causes of bleeding in WAS patients. However, the molecular bases underlying these defects are unclear. This study focuses on the molecular mechanism of defective platelet aggregation of WAS patients. The gene responsible for WAS encodes WAS protein (WASP). The mutations or deletion of WASP causes various functional defects in hematopoietic cells. We previously showed that binding of WASP to calcium- and integrin-binding protein (CIB) is required for activation of platelet integrin, αIIbβ3. I here demonstrate that blocking WASP binding to CIB reduces binding of talin to the β3 cytoplasmic tail, resulting in impaired activation of αIIbβ3. Impaired αIIbβ3 activation causes defective platelet aggregation, resulting in bleeding. This finding suggests a potential disease mechanism underlying bleeding seen in WAS patients.
Article Commentary: Insulin Resistance, Type 2 Diabetes and Chronic Liver Disease. A Deadly Trio
Authors: Lonardo Amedeo , Loria Paola
Published: October 2017

In this commentary to the paper by Donadon V. et al (Clinical Medicine: Endocrinology and Diabetes. 2009;2:25–33.) the association and significance of insulin resistance with chronic liver disease are shortly reviewed and the molecular mechanisms underlying the diabetogenic and oncogenic potentials of advanced liver disease are summarized. Literature studies demonstrate that hepatocellular carcinoma (HCC) can be part of the natural history of NASH. HCCs in patients with features of metabolic syndrome as the only risk factor for liver disease have distinct morphological characteristics and mainly occur in the absence of significant fibrosis in the background liver. Moreover, data indicate that the presence of diabetes carries an approximately three to four-fold increased risk of HCC and such a risk is strongly increased by concurrent viral infections. Finally, the relationship between insulin resistance, steatosis and diabetes in NAFLD and HCV infection will be commented, along with the directions for future studies.
Diabetes Mellitus as Dysfunction of Interactions among all Organs: “Ominous Orchestra of Organs”
Authors: Koshiyama Hiroyuki , Ogawa Yoshihiro , Tanaka Kiyoshi , Tanaka Issei
Published: October 2017

Epidemiological evidence has established a link among hyperlipidemia, visceral obesity, osteoporosis, and cardiovascular diseases. We have recently proposed a hypothesis that the associations of those disorders are based on interactions of the three organs, i.e. the bone, adipose, and vascular tissues, possibly through multiple actions of several humoral factors and/or transcription factors. We call this unified hypothesis “osteo-lipo-vascular interactions”, which may be explained by the common origin of the cells in each organ, such as mesenchymal stem cells or macrophages. Several groups proposed similar hypotheses. On the other hand, there have been accumulating evidences which indicate that there exist hitherto unknown various interactions between many organs, such as hypothalamus-liver, fat-liver, liver-muscle, intestine-pancreas, kidney-heart and so on. Therefore, it seems insufficient to consider only the interactions among several organs, and the standpoint of considering interactions among all organs may be warranted, especially in order to understand the pathogenesis of metabolic syndrome, insulin resistance and type 2 diabetes. We here propose a hypothesis that the abnormal interactions of all organs (“Ominous Orchestra of Organs”) underlies the pathogenesis of type 2 diabetes. It is to be elucidated which of the “players” or the “conductor” may be mainly responsible for disharmony of the orchestra.
Biomarkers for Cancers of the Head and Neck
Authors: Lutzky Viviana P. , Moss Denis J. , Chin David , Coman William B. , Parsons Peter G. , Boyle Glen M.
Published: October 2017

Head and neck cancer is a broad term used to describe malignancies that arise in the nasal and oral cavities, pharynx and larynx, as well as the paranasal sinuses. Head and neck squamous cell carcinoma (HNSCC) affects the squamous epithelium of the oral cavity, tongue and oropharynx, excluding the nasopharynx. Recent advances in molecular technology, including gene expression and proteomic profiling appear to offer the potential for the development of specific biomarkers including diagnostic tools which may act as an aid to guide therapy for this malignancy. The other human head and neck cancer included in this review, nasopharyngeal carcinoma (NPC) is a malignancy derived from the undifferentiated epithelium of the nasopharyngeal cavity, and is considered here as a separate entity because its strong association with Epstein-Barr virus (EBV) presents the opportunity for the development of virus related and unrelated biomarkers. In particular, IgA antibodies to EBV and high levels of EBV DNA in serum samples of NPC patients have been recorded. This review aims to summarize some current and also potential new biomarkers that could be used for screening, diagnosis, monitoring and prognostic prediction for cancers of the head and neck, including NPC and HNSCC.
Hemangioma of the Thyroid
Authors: Sakai Akihiro , Sugitani Iwao , Yamamoto Noriko , Kawabata Kazuyoshi
Published: October 2017

Introduction

Thyroid hemangioma is very rare, and only a few cases have previously been reported. We encountered a patient with thyroid hemangioma diagnosed after surgery.

Case Report

A 71-year-old woman visited our hospital with a mass in the left thyroid region. A 5-cm, elastic mass of the thyroid was palpable in the left anterior neck. On cytology by fine-needle aspiration (FNA), the specimen mainly contained blood components without apparent atypical cells. A tumor with abundant blood flow was suspected based on Doppler ultrasonography. Adenomatous goiter was suspected, and subtotal thyroidectomy was performed. A blood clot was present in the tumor, and hemangioma was diagnosed on postoperative histopathological examination.

Discussion

Preoperative diagnosis of thyroid hemangioma is difficult. However, Doppler ultrasonography and FNA are useful for diagnosis. A differential diagnosis of hemangioma should be considered when blood flow is abundant and only blood components are collected.
Sharp stability inequalities for planar double bubbles
Authors: Cicalese Marco , Leonardi Gian Paolo , Maggi Francesco
Published: October 2017

In this paper we address the global stability problem for double-bubbles in the plane. This is accomplished by combining the
improved convergence theorem
for planar clusters developed in [8] with an ad hoc analysis of the problem, which addresses the delicate interaction between the (possible) dislocation of singularities and the multiple-volumes constraint.
Some results on anisotropic fractional mean curvature flows
Authors: Chambolle Antonin , Novaga Matteo , Ruffini Berardo
Published: October 2017

We show the consistency of a threshold dynamics type algorithm for the anisotropic motion by fractional mean curvature, in the presence of a time dependent forcing term. Beside the consistency result, we show that convex sets remain convex during the evolution, and the evolution of a bounded convex set is uniquely defined.
Real-Time Polymerase Chain Reaction Assay on Bronchoalveolar Lavage: An Alternative Method for Diagnosing Chronic Pulmonary Schistosomiasis?
Authors: Gobbi Federico , Formenti Fabio , Perandin Francesca , Buonfrate Dora , Angheben Andrea , Paiano Simona , Bisoffi Zeno
Published: October 2017

Schistosomiasis causes mainly hepatic and genitourinary damage. Although lung nodules have been commonly described in acute phase, they are presumably underdiagnosed in chronic schistosomiasis. We previously reported a series of patients with chronic pulmonary schistosomiasis confirmed by the histological examination of the lung biopsies. In the present work, we retrospectively tested an in-house real-time polymerase chain reaction for Schistosoma (currently validated for diagnosis on stool and on urine) in the bronchoalveolar lavage (BAL) of a couple of those patients, and both resulted positive. The possibility of testing BAL with molecular methods targeting a wide spectrum of pathogens, including parasites, is appealing. Further studies are needed to validate this technique that might reduce unnecessary biopsies.
Source attribution of Arctic black carbon constrained by aircraft and surface measurements
Authors: Xu Jun-Wei , Martin Randall V. , Morrow Andrew , Sharma Sangeeta , Huang Lin , Leaitch W. Richard , Burkart Julia , Schulz Hannes , Zanatta Marco , Willis Megan D. , Henze Daven K. , Lee Colin J. , Herber Andreas B. , Abbatt Jonathan P. D.
Published: October 2017

Abstract. Black carbon (BC) contributes to Arctic warming, yet sources of Arctic BC and their geographic contributions remain uncertain. We interpret a series of recent airborne (NETCARE 2015; PAMARCMiP 2009 and 2011 campaigns) and ground-based measurements (at Alert, Barrow and Ny-Ålesund) from multiple methods (thermal, laser incandescence and light absorption) with the GEOS-Chem global chemical transport model and its adjoint to attribute the sources of Arctic BC. This is the first comparison with a chemical transport model of refractory BC (rBC) measurements at Alert. The springtime airborne measurements performed by the NETCARE campaign in 2015 and the PAMARCMiP campaigns in 2009 and 2011 offer BC vertical profiles extending to above 6 km across the Arctic and include profiles above Arctic ground monitoring stations. Our simulations with the addition of seasonally varying domestic heating and of gas flaring emissions are consistent with ground-based measurements of BC concentrations at Alert and Barrow in winter and spring (rRMSE  < 13 %) and with airborne measurements of the BC vertical profile across the Arctic (rRMSE  = 17 %) except for an underestimation in the middle troposphere (500–700 hPa).Sensitivity simulations suggest that anthropogenic emissions in eastern and southern Asia have the largest effect on the Arctic BC column burden both in spring (56 %) and annually (37 %), with the largest contribution in the middle troposphere (400–700 hPa). Anthropogenic emissions from northern Asia contribute considerable BC (27 % in spring and 43 % annually) to the lower troposphere (below 900 hPa). Biomass burning contributes 20 % to the Arctic BC column annually.At the Arctic surface, anthropogenic emissions from northern Asia (40–45 %) and eastern and southern Asia (20–40 %) are the largest BC contributors in winter and spring, followed by Europe (16–36 %). Biomass burning from North America is the most important contributor to all stations in summer, especially at Barrow.Our adjoint simulations indicate pronounced spatial heterogeneity in the contribution of emissions to the Arctic BC column concentrations, with noteworthy contributions from emissions in eastern China (15 %) and western Siberia (6.5 %). Although uncertain, gas flaring emissions from oilfields in western Siberia could have a striking impact (13 %) on Arctic BC loadings in January, comparable to the total influence of continental Europe and North America (6.5 % each in January). Emissions from as far as the Indo-Gangetic Plain could have a substantial influence (6.3 % annually) on Arctic BC as well.
Impact of surface and near-surface processes on ice crystal concentrations measured at mountain-top research stations
Authors: Beck Alexander , Henneberger Jan , Fugal Jacob P. , David Robert O. , Lacher Larissa , Lohmann Ulrike
Published: October 2017

Abstract. In-situ cloud observations at mountain-top research stations regularly measure ice crystal number concentrations (ICNCs) orders of magnitudes higher than expected from measurements of ice nucleating particle (INP) concentrations. Thus, several studies suggest that mountain-top in-situ measurements are influenced by surface processes, e.g. blowing snow, hoar frost or riming on snow covered trees, rocks and the snow surface. A strong impact on the observed ICNCs on mountain-top stations by surface processes may limit the relevance of such measurements and possibly affects the development of orographic clouds. This study assesses the impact of surface processes on in-situ cloud observations at the Sonnblick Observatory in the Hohen Tauern Region, Austria. Vertical profiles of ICNCs above a snow covered surface were observed up to a height of 10 m. The ICNC decreases at least by a factor of two at 10 m, if the ICNC at the surface is larger than 100 L−1. This decrease can be up to one order of magnitude during in-cloud conditions and reached its maximum of more than two orders of magnitudes when the station was not in cloud. For one case study, the ICNC for regular and irregular ice crystals showed a similar relative decrease with height, which cannot be explained by the above mentioned surface processes. Therefore, two near-surface processes are proposed to enrich ICNCs and explain these finding. Either sedimenting ice crystals are captured in a turbulent layer above the surface or the ICNC is enhanced in a convergence zone, because the cloud is forced over a mountain. These two processes would also have an impact on ICNCs measured at mountain-top stations if the surrounding surface is not snow covered. Conclusively, this study strongly suggests that ICNCs measured at mountain-top stations are not representative for the properties of a cloud further away from the surface.
Three-channel single-wavelength lidar depolarization calibration
Authors: McCullough Emily M. , Sica Robert J. , Drummond James R. , Nott Graeme , Perro Christopher , Duck Tom J.
Published: October 2017

Abstract. Linear depolarization measurement capabilities were added to the CANDAC Rayleigh-Mie-Raman lidar (CRL) at Eureka, Nunavut, in the Canadian High Arctic in 2010. This upgrade enables measurements of the phases (liquid versus ice) of cold and mixed-phase clouds throughout the year, including during polar night. Depolarization measurements were calibrated according to existing methods using parallel- and perpendicular-polarized profiles as discussed in McCullough et al. (2017). We present a new technique that uses the polarization-independent Rayleigh elastic channel in combination with one of the new polarization-dependent channels, and show that for a lidar with low signal in one of the polarization-dependent channels, this method is superior to the traditional method. The optimal procedure for CRL is to determine the depolarization parameter using the traditional method at low resolution (from parallel and perpendicular signals), and then to use this value to calibrate the high-resolution new measurements (from parallel and polarization-independent Rayleigh elastic signals). Due to its use of two high-signal-rate channels, the new method has lower statistical uncertainty, and thus gives depolarization parameter values at higher spatial-temporal resolution by up to a factor of 20 for CRL. This method is easily adaptable to other lidar systems which are considering adding depolarization capability to existing hardware.
Exploring femtosecond laser ablation in single particle aerosol mass spectrometry
Authors: Ramisetty Ramakrishna , Abdelmonem Ahmed , Shen Xiaoli , Saathoff Harald , Leisner Thomas , Mohr Claudia
Published: October 2017

Abstract. Size, composition, and mixing state of individual aerosol particles can be analysed in real time using single particle mass spectrometry (SPMS). In SPMS, laser ablation is the most widely used method for desorption and ionization of particle components, often realizing both in one single step. Excimer lasers are well suited for this task due to their relatively high power density (107 W cm−2–1010 W cm−2) in nanosecond (ns) pulses at ultraviolet (UV) wavelengths, and short triggering times. However, varying particle optical properties and matrix effects make a quantitative interpretation of this analytical approach challenging. In atmospheric SPMS applications, this influences both the mass fraction of an individual particle that gets ablated, as well as the resulting mass spectral fragmentation pattern of the ablated material. The goal of the present study is to explore the use of shorter (femtosecond, fs) laser pulses for atmospheric SPMS, and to systematically investigate the influence of power density and pulse duration on airborne particle (polystyrene latex, SiO2, NH4NO3, NaCl, and custom-made core-shell particles) ablation and reproducibility of mass spectral signatures. We used a laser ablation aerosol time-of-flight single particle mass spectrometer (LAAPTOF, AeroMegt GmbH), originally equipped with an excimer laser (wavelength 193 nm, pulse width 8 ns, pulse energy 4 mJ), and coupled it to an fs-laser (Spectra Physics Solstice-100F ultrafast laser) with similar pulse energy, but longer wavelengths (266 nm with 100 fs and 0.2 mJ, 800 nm with 100 fs and 4 mJ, respectively). Generally, mass spectra exhibit an increase in ion intensities (factor 1 to 5) with increasing laser power density (~ 108 W cm−2 to ~ 1013 W cm−2) from ns- to fs-laser. At the same time, fs-laser ablation produces spectra with larger ion fragments and ion clusters, as well as clusters with oxygen, which does not render spectra interpretation more simple compared to ns-laser ablation. Quantification of ablated material remains difficult due to incomplete ionization of the particle. Furthermore, the fs-laser application still suffers from limitations in triggering it in a useful timeframe. Further tests are needed to test potential advantages of fs- over ns-laser ablation in atmospheric SPMS.
Two drastically different climate states on an Earth-like terra-planet
Authors: Kalidindi Sirisha , Reick Christian H. , Raddatz Thomas , Claussen Martin
Published: October 2017

Abstract. We study an Earth-like terra-planet with an overland recycling mechanism bringing fresh water back from higher latitudes to the lower latitudes. By performing model simulations for such a planet we find two drastically different climate states for the same set of boundary conditions and parameter values: A Cold and Wet (CW) state (present-day Earth-like climate) with dominant low-latitude precipitation and, a Hot and Dry (HD) state with only high-latitude precipitation. We notice that for perpetual equinox conditions, both climate states are stable below a certain threshold value of background soil albedo while above the threshold only the CW state is stable. Starting from the HD state and increasing background soil albedo above the threshold causes an abrupt shift from the HD state to the CW state resulting in a sudden cooling of about 35 °C globally which is of the order of the temperature difference between the present-day and the Snowball Earth state. In contrast to the Snowball Earth instability, we find that the sudden cooling in our study is driven by the cloud albedo feedback rather than the snow-albedo feedback. Also, when albedo in the CW state is reduced back to zero the terra-planet does not display a closed hysteresis. This is due to the high cloud cover in the CW state hiding the surface from solar irradiation. As a result, this reduction of background surface albedo has only a minor effect on the top of the atmosphere radiation balance, thereby making it impossible to heat the planet sufficiently strongly to switch back to the HD state. Additional simulations point to a similar abrupt transition from HD state to the CW state for non-zero obliquity which is the only stable state in this configuration. Our study also has implications for the habitability of Earth-like terra-planets. At the inner edge of the habitable zone, the higher cloud cover in the CW state cools the planet and may prevent the onset of a runaway greenhouse state. At the outer edge, the resupply of water at lower latitudes stabilizes the greenhouse effect and keeps the planet in the HD state and may prevent water from getting trapped at higher latitudes in frozen form. Overall, the existence of bi-stability in the presence of an overland recycling mechanism hints at the possibility of a wider habitable zone for Earth-like terra-planets at lower obliquities.
Modelling soil CO2 production and transport with dynamic source and diffusion terms: Testing the steady-state assumption using DETECT v1.0
Authors: Ryan Edmund , Ogle Kiona , Kropp Heather , Samuels-Crow Kimberly E. , Carrillo Yolima , Pendall Elise
Published: October 2017

Abstract. The flux of CO2 from the soil to the atmosphere (soil respiration, Rsoil) is a major component of the global carbon cycle. Methods to measure and model Rsoil, or partition it into different components, often rely on the assumption that soil CO2 concentrations and fluxes are in steady state, implying that Rsoil is equal to the rate at which CO2 is produced by soil microbial and root respiration. Recent research, however, questions the validity of this assumption. Thus, the aim of this work was two-fold: (1) to describe a non-steady state (NSS) soil CO2 transport and production model, DETECT, and (2) to use this model to evaluate the environmental conditions under which Rsoil and CO2 production are likely in NSS. The backbone of DETECT is a non-homogeneous, partial differential equation (PDE) that describes production and transport of soil CO2, which we solve numerically at fine spatial and temporal resolution (e.g., 0.01 m increments to 1 m, every 6 hours). Production of soil CO2 is simulated for every depth and time increment as the sum of root respiration and microbial decomposition of soil organic matter, both of which can be driven by current and antecedent soil water content and temperature, which can also vary by time and depth. We also analytically solved the ordinary differential equation (ODE) corresponding to the steady-state (SS) solution to the PDE model. We applied the DETECT NSS and SS models to the 6-month growing season period representative of a native grassland in Wyoming. Simulation experiments were conducted with both model versions to evaluate factors that could affect departure from SS: (1) varying soil texture; (2) shifting the timing or frequency of precipitation; and (3) with and without the environmental antecedent drivers. For a coarse-textured soil, Rsoil from the SS model closely matched that of the NSS model. However, in a fine-textured (clay) soil, growing season Rsoil was ~ 3 % higher under the assumption of NSS (versus SS). These differences were exaggerated in clay soil at daily time-scales whereby Rsoil under the SS assumption deviated from NSS by up to ~ 20 % in the 10 days following a major precipitation event. Moreover, incorporation of antecedent drivers increased the magnitude of Rsoil by 15 % to 37 % for coarse- and fine-textured soils, respectively. However, the responses of Rsoil to the timing of precipitation and antecedent drivers did not differ between SS and NSS assumptions. In summary, the assumption of SS conditions can be violated depending on soil type and soil moisture status, as affected by precipitation inputs, and the DETECT model provides a framework for accommodating NSS conditions to better predict Rsoil and associated soil carbon cycling processes.
HYDROTHEMAL ALTERATION MAPPING USING FEATURE-ORIENTED PRINCIPAL COMPONENT SELECTION (FPCS) METHOD TO ASTER DATA:WIKKI AND MAWULGO THERMAL SPRINGS, YANKARI PARK, NIGERIA
Authors: Abubakar A. J. , Hashim M. , Pour A. B.
Published: October 2017

Abstract. Geothermal systems are essentially associated with hydrothermal alteration mineral assemblages such as iron oxide/hydroxide, clay, sulfate, carbonate and silicate groups. Blind and fossilized geothermal systems are not characterized by obvious surface manifestations like hot springs, geysers and fumaroles, therefore, they could not be easily identifiable using conventional techniques. In this investigation, the applicability of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) were evaluated in discriminating hydrothermal alteration minerals associated with geothermal systems as a proxy in identifying subtle Geothermal systems at Yankari Park in northeastern Nigeria. The area is characterized by a number of thermal springs such as Wikki and Mawulgo. Feature-oriented Principal Component selection (FPCS) was applied to ASTER data based on spectral characteristics of hydrothermal alteration minerals for a systematic and selective extraction of the information of interest. Application of FPCS analysis to bands 5, 6 and 8 and bands 1, 2, 3 and 4 datasets of ASTER was used for mapping clay and iron oxide/hydroxide minerals in the zones of Wikki and Mawulgo thermal springs in Yankari Park area. Field survey using GPS and laboratory analysis, including X-ray Diffractometer (XRD) and Analytical Spectral Devices (ASD) were carried out to verify the image processing results. The results indicate that ASTER dataset reliably and complementarily be used for reconnaissance stage of targeting subtle alteration mineral assemblages associated with geothermal systems.
THE EFFECTS OF BUILT-UP AND GREEN AREAS ON THE LAND SURFACE TEMPERATURE OF THE KUALA LUMPUR CITY
Authors: Isa N. A. , Wan Mohd W. M. N. , Salleh S. A.
Published: October 2017

Abstract. A common consequence of rapid and uncontrollable urbanization is Urban Heat Island (UHI). It occurs due to the negligence on climate behaviour which degrades the quality of urban climate condition. Recently, addressing urban climate in urban planning through mapping has received worldwide attention. Therefore, the need to identify the significant factors is a must. This study aims to analyse the relationships between Land Surface Temperature (LST) and two urban parameters namely built-up and green areas. Geographical Information System (GIS) and remote sensing techniques were used to prepare the necessary data layers required for this study. The built-up and the green areas were extracted from Landsat 8 satellite images either using the Normalized Difference Built-Up Index (NDBI), Normalized Difference Vegetation Index (NDVI) or Modified Normalize Difference Water Index (MNDWI) algorithms, while the mono-window algorithm was used to retrieve the Land Surface Temperature (LST). Correlation analysis and Multi-Linear Regression (MLR) model were applied to quantitatively analyse the effects of the urban parameters. From the study, it was found that the two urban parameters have significant effects on the LST of Kuala Lumpur City. The built-up areas have greater influence on the LST as compared to the green areas. The built-up areas tend to increase the LST while green areas especially the densely vegetated areas help to reduce the LST within an urban areas. Future studies should focus on improving existing urban climatic model by including other urban parameters.
SINKHOLE SUSCEPTIBILITY HAZARD ZONES USING GIS AND ANALYTICAL HIERARCHICAL PROCESS (AHP): A CASE STUDY OF KUALA LUMPUR AND AMPANG JAYA
Authors: Rosdi M. A. H. M. , Othman A. N. , Zubir M. A. M. , Latif Z. A. , Yusoff Z. M.
Published: October 2017

Abstract. Sinkhole is not classified as new phenomenon in this country, especially surround Klang Valley. Since 1968, the increasing numbers of sinkhole incident have been reported in Kuala Lumpur and the vicinity areas. As the results, it poses a serious threat for human lives, assets and structure especially in the capital city of Malaysia. Therefore, a Sinkhole Hazard Model (SHM) was generated with integration of GIS framework by applying Analytical Hierarchical Process (AHP) technique in order to produced sinkhole susceptibility hazard map for the particular area. Five consecutive parameters for main criteria each categorized by five sub classes were selected for this research which is Lithology (LT), Groundwater Level Decline (WLD), Soil Type (ST), Land Use (LU) and Proximity to Groundwater Wells (PG). A set of relative weights were assigned to each inducing factor and computed through pairwise comparison matrix derived from expert judgment. Lithology and Groundwater Level Decline has been identified gives the highest impact to the sinkhole development. A sinkhole susceptibility hazard zones was classified into five prone areas namely very low, low, moderate, high and very high hazard. The results obtained were validated with thirty three (33) previous sinkhole inventory data. This evaluation shows that the model indicates 64 % and 21 % of the sinkhole events fall within high and very high hazard zones respectively. Based on this outcome, it clearly represents that AHP approach is useful to predict natural disaster such as sinkhole hazard.
TARGETING HYDROTHERMAL ALTERATIONS UTILIZING LANDSAT-8 ANDASTER DATA IN SHAHR-E-BABAK, IRAN
Authors: Safari M. , Pour A. B. , Maghsoudi A. , Hashim M.
Published: October 2017

Abstract. Shahr-e-Babak tract of the Kerman metalogenic belt is one of the most potential segments of Urumieh–Dokhtar (Sahand-Bazman) magmatic arc. This area encompasses several porphyry copper deposits in exploration, development and exploitation hierarchy. The aim of this study is to map hydrothermal alterations caused by early Cenozoic magmatic intrusions in Shahr-e-Babak area. To this purpose, mineral mapping methods including band combinations, ratios and multiplications as well as PCA and MNF data space transforms in SWIR and VNIR for both ASTER and OLI sensors. Alteration zones according to spectral signatures of each type of alteration mineral assemblages such as argillic, phyllic and propylitic are successfully mapped. For enhancing the target areas false color composites and HSI-RGB color space transform are performed on developed band combinations. Previous studies have proven the robust application of ASTER in geology and mineral exploration; nonetheless, the results of this investigation prove applicability of OLI sensor from landsat-8 for alteration mapping. According to the results, evidently OLI sensor data can accurately map alteration zones. Additionally, the 12-bit quantization of OLI data is its privilege over 8-bit data of ASTER in VNIR and SWIR, thus OLI high quality results, which makes it easy to distinguish targets with enhanced color contrast between the altered and unaltered rocks.
SPATIO-TEMPORAL ESTIMATION OF INTEGRATED WATER VAPOUR OVER THE MALAYSIAN PENINSULA DURING MONSOON SEASON
Authors: Salihin S. , Musa T. A. , Mohd Radzi Z.
Published: October 2017

Abstract. This paper provides the precise information on spatial-temporal distribution of water vapour that was retrieved from Zenith Path Delay (ZPD) which was estimated by Global Positioning System (GPS) processing over the Malaysian Peninsular. A time series analysis of these ZPD and Integrated Water Vapor (IWV) values was done to capture the characteristic on their seasonal variation during monsoon seasons. This study was found that the pattern and distribution of atmospheric water vapour over Malaysian Peninsular in whole four years periods were influenced by two inter-monsoon and two monsoon seasons which are First Inter-monsoon, Second Inter-monsoon, Southwest monsoon and Northeast monsoon.