Filter Station Research Articles

Comparison of efficiency for steel and combined frames

Recently, in the practice of design, customers of design works and investors of various projects have a dilemma regarding the choice of building material for load-bearing building structures. At the same time, the choice is usually limited to two types of materials – steel and reinforced concrete. Each of these materials has its advantages and disadvantages, which results in their different efficiency of application for various types of building structures. At the same time, the main attention is paid to the estimation side, because in modern complex and dynamic conditions, it turns out to be dominant in many cases. 
 The article presents the results of research of the completed master's thesis on the comparative analysis of the effectiveness of steel and combined frames (steel-reinforced concrete) on the example of the filter station building. The building has dimensions in plan of 54 × 36 m with a total height of about 22 m. Its supporting frame is a statically nondefined flat frame consisting of columns and crossbars in the form of trusses. In the longitudinal direction of the building, the frames are united into a spatial system by means of covering structures. The building is craneless and has three floors, each about 6.5 m high. 
 In the course of research, the considered variants of the transverse frame were analyzed using the finite element method on the basis of the LIRA-CAD multifunctional design complex. As a result, appropriate cross-sections for loads according to the climatic conditions of Ukraine were obtained. A comparison of variants showed that the first design variant is 9 % cheaper. Taking into account the additional technological advantages in its manufacture, the steel frame can be considered more effective for the given construction conditions and be recommended for practical implementation. Separately, it should be noted that such a frame also has an average of 5 times less total mass, which should be considered its additional advantage.

Environmental aspects of the use of pressure filters for water purification of reservoirs in drinking water supply systems

The experience of designing and operating water treatment facilities for natural surface sources for the needs of populated areas and industrial enterprises in countries with developed industry allows us to conclude that it is advisable to purify water with a suspended solids content of up to 100-150 g/m3 using filtration methods. Therefore, the introduction into the practice of designing water treatment methods that ensure the use of compact, high-performance, automatically controlled structures acquires national economic importance. Filter stations equipped with pressure filters operating in the ultra-high-speed filtration mode meet these requirements to the greatest extent. The object of this study is a vertical pressure filter with an upward flow of purified water and a clamped filter layer. The applied research methods include the analysis of literature sources on the topic under study, experimental studies performed in a laboratory installation that fully simulates the technological scheme being developed, etc. The purpose of the study is to determine the effectiveness of the use of pressure filters with an upward flow and a clamped load for the purification of natural waters containing up to 100-120 g/m3 of suspended solids, and to develop recommendations for their use in the conditions of the Uzbekistan Republic. Laboratory tests of ultra-high-speed pressure filtration with an ascending flow have proved the high retention capacity of loading from local granular materials when filtering the purified water in the direction of decreasing grain size. Thus, the effect of water purification to remove suspended solids during the inter-washing period of the filter, which reached 10-18 hours, was stable and amounted to 87-97 percent.

Optimization of water filter station locations on polluted rivers of Jakarta

Flooding has always been one of the challenging problems Jakarta faces for decades, damaging not only the infrastructure but also the economic aspects of the city. Almost every year, significant losses are recorded in both parts, including for the residents who depend on it. One of the repressive steps for flood prevention is the placement of waste filtering stations on the rivers in multiple locations. According to the Ministry of Environment and Forestry representative for Jakarta, there are currently 28 waste filtering stations installed within Jakarta's 661.5 km2 region and 13 rivers. Continuously challenged with the increasing amount of waste, flood prevention efforts must include installing more filtering stations. Therefore, studying the optimum future station location to minimize the flooding hazard effectively becomes vital. This paper utilized the Hot Spot Spatial Analysis method to estimate several optimal areas that fit the criterion of previously built filtering stations. We obtained the local hotspot statistics for each parameter from the Getis-Ord local statistics equation. In addition, many necessary layers are also utilized, such as volume of waste filter points, population density, and flood-affected areas datasets to roughly approximate the real-world condition. This study aims to provide recommendations that can determine the optimal waste filtering points and provide a better solution for Jakarta from the problem of the harmful amount of waste in the river that could induce flooding hazards. The result shows that the waste filtering stations in the 13 major rivers in Jakarta are still not effective. This research helps to show the optimal locations suitable for constructing new waste filters.

The Use of a Fault Tree Analysis (FTA) in the Operator Reliability Assessment of the Critical Infrastructure on the Example of Water Supply System

Background: Specialist literature indicates a large share of the human factor among the causes of failure of technical systems at the level of 70 to 90%, which depends on the sector studied. The collective water supply system is an anthropotechnical system, i.e., it is a complex connection between man and the technical system resulting from the deliberate influence of man on the technical system. Methods: The work presents an assessment of operator reliability of a selected water treatment process based on the fault tree analysis (FTA). Elementary events are determined by the operator’s error probability. Results: A failure tree was prepared for the peak event of the filter station failure, resulting from an operator’s error during the filter washing procedure. The probability of a peak event occurring is 0.0580. Conclusions: The developed fault tree allows for the identification of elementary events leading to an emergency event. The operator fulfills its task of maintaining the continuity of water treatment.

Comparing model skills for deterministic versus ensemble dispersion modelling: The Fukushima Daiichi NPP accident as a case study

Atmospheric dispersion models are crucial for nuclear risk assessment and emergency response systems since they rapidly predict air concentrations and deposition of released radionuclides, providing a basis for dose estimations and countermeasure strategies. Atmospheric dispersion models are associated with relatively large and often unknown uncertainties that are mostly attributed to meteorology, source terms and parametrisation of the dispersion model. By developing methods that can provide reliable uncertainty ranges for model outputs, decision makers have an improved basis for handling nuclear emergency situations.In the present work, model skill of the Severe Nuclear Accident Programme (SNAP) model was quantified by employing an ensemble method in which 51 meteorological realisations from a numerical weather prediction model were combined with 9 source term descriptions for the accidental 137Cs releases from Fukushima Daiichi Nuclear Power Plant during 14th–17th March 2011. The meteorological forecast was compared to observations of wind speed from 30 meteorological stations.The 459 dispersion realisations were compared with hourly observations of activity concentrations from 100 air filter stations. Exclusive use of deterministic meteorology resulted in most members of the dispersion ensemble showing too low concentration values, however this was mitigated by applying ensemble meteorology. Ensemble predictions, including both the meteorological and source term ensemble, show an overall higher prediction skill compared to individual meteorology and source term runs, with true predictive rate accuracy increasing from 30%–50% to 70%–90%, with a decrease in positive predictive rate accuracy from 75%–80% to 65%–75%. Skill scores and other ensemble indicators also showed improvements in using ensembles of source terms and meteorology. From the present study on the Fukushima accident there are strong indications that ensemble predictions improve the basis for decision making in the early phase after a nuclear accident, which emphasises the importance of including ensemble prediction in nuclear preparedness tools of the future.

Robust estimation of spatially varying common-mode components in GPS time-series

We present a new method to estimate common-mode components (CMC) in global positioning system (GPS) position time-series. The method (‘CMC Imaging’) is fully automated, relies entirely on robust statistics, and exploits the recent proliferation of GPS stations by allowing stations with relatively short time-series to be considered as filter stations as well. The spatial extent of the CMC is purposely defined as local as possible and constrained by the proximity of nearby GPS stations. Our approach also avoids the need for subjective assignment of filter stations; every station is considered and those stations that deviate significantly from the local CMC are flagged and excluded as filter stations. We study thousands of GPS position time-series in the intraplate area of western Europe, and we show that CMC Imaging method is superior to other approaches in terms of noise reduction: we obtain an RMS reduction of 50%, 44% and 39% in the residual time-series in vertical, east, and north components, respectively. We show the importance of using filter stations that are as local as possible, because of systematic lateral variations in inter-station correlations and indeed in CMC, particularly in the vertical component. Those spatial variations are largest for continental stations, particularly those around the Baltic Sea, and could be due to atmospheric and nontidal ocean loading. CMC filtering has a large influence on reducing the temporal trend variability and approximately doubles the trend accuracy (by comparing variability in short-term trends with the long-term estimate).

Growth and biomass yield of hydroponically grown thyme (Thymus vulgaris L.) in response to brackish water‐induced stress*

AbstractReuse of non‐traditional water (brackish water) in agriculture will reduce the cost of disposal. On the other hand, the use of brackish water may cause environmental pollution to the soil, groundwater and plants after being discharged to the soil. The purpose of the current study was to assess the effect of reusing filter station water on the growth and yield of thyme plants during three growing seasons, 2014–2016. Three types of irrigation water were used in the current study: fresh tap water (T1), mixed water (T2) and brackish water (T3), with total dissolved solids (TDS) of 500, 1500 and 2500 ppm, respectively. Number of lateral leaves, plant height (cm) and fresh and dry weights (g m¯2) were recorded. In addition, the percentage of nitrogen (N), phosphorus (P), potassium (K) and calcium (Ca) in the leaves was determined. Results showed that plant parameters as well as yield were affected by mixed and brackish water. In addition, the chemical composition of leaves was affected significantly by the treatments. © 2020 John Wiley & Sons, Ltd.

Estimation of GPS Differential Code Biases Based on Independent Reference Station and Recursive Filter

The differential code bias (DCB) of the Global Navigation Satellite Systems (GNSS) receiver should be precisely corrected when conducting ionospheric remote sensing and precise point positioning. The DCBs can usually be estimated by the ground GNSS network based on the parameterization of the global ionosphere together with the global ionospheric map (GIM). In order to reduce the spatial-temporal complexities, various algorithms based on GIM and local ionospheric modeling are conducted, but rely on station selection. In this paper, we present a recursive method to estimate the DCBs of Global Positioning System (GPS) satellites based on a recursive filter and independent reference station selection procedure. The satellite and receiver DCBs are estimated once per local day and aligned with the DCB product provided by the Center for Orbit Determination in Europe (CODE). From the statistical analysis with CODE DCB products, the results show that the accuracy of GPS satellite DCB estimates obtained by the recursive method can reach about 0.10 ns under solar quiet condition. The influence of stations with bad performances on DCB estimation can be reduced through the independent iterative reference selection. The accuracy of local ionospheric modeling based on recursive filter is less than 2 Total Electron Content Unit (TECU) in the monthly median sense. The performance of the recursive method is also evaluated under different solar conditions and the results show that the local ionospheric modeling is sensitive to solar conditions. Moreover, the recursive method has the potential to be implemented in the near real-time DCB estimation and GNSS data quality check.

Design and Software Implementation of Analog and Digital Filters For Coherent Receivers under Noisy Channels

One of the most important stations in any communications system is the filtering station. Due to the noise power that effects on the signal, the system must include filtering process to eliminate this effect. In this paper, analog and digital filters are designed and implemented using Matlab tools to solve the problems occurred during receiving the signal that effects on the synchronization such as those for coherent receivers. The offsets of Phase and frequency are major problems in the identification of signals that results reduction in the performance; such as, whenever higher order modulations are used. Two systems are designed and simulated. The first one is analog system and the second one is digital system. 3rd order Butterworth filter is selected for system one and digital IIR filter is selected for system two. Filter order was selected according to diagnosis the level of noise power and the transmitted frequency to meet certain frequency domain design specifications. Obtained results showed excellent performance in the receiving and demodulating the received signal. Evaluation of the results is basically depend on comparison between the transmitted and received samples.

Effect of Header-based Features on Accuracy of Classifiers for Spam Email Classification

Emails are an integral part of communication in today’s world. But Spam emails are a hindrance, leading to reduction in efficiency, security threats and wastage of bandwidth. Hence, they need to be filtered at the first filtering station, so that employees are spared the drudgery of handling them. Most of the earlier approaches are mainly focused on building content-based filters using body of an email message. Use of selected header features to filter spam, is a better strategy, which was initiated by few researchers. In this context, our research intends to find out minimum number of features required to classify spam and ham emails. A set of experiments was conducted with three datasets and five Feature Selection techniques namely Chi-square, Correlation, Relief Feature Selection, Information Gain, and Wrapper. Five-classification algorithms-Naive Bayes, Decision Tree, NBTree, Random Forest and Support Vector Machine were used. In most of the approaches, a trade-off exists between improper filtering and number of features. Hence arriving at an optimum set of features is a challenge. Our results show that in order to achieve the objective of satisfactory filtering, minimum 5 and maximum 14 features are required.

Using KDF material to improve the performance of multi-layers filters in the reduction of chemical and biological pollutants in surface water treatment

Multi-layers filters are usually used in conventional water treatment plants to purify water, reduce turbidity, and remove plankton and undesired odours. Multi-layers filter consists of basic layers represented in graded sand and supporting gravel layers. This research aims to study the efficiency of such filters after the addition of new layers made of copper and zinc particles by 50% per each with high purity, which are traditionally called KDF (Kinetic Degradation Fluxion). The purpose of adding such layers is to increase the efficiency of filters in the removal of diverse chemical contaminants of heavy elements (Lead, Nickel, iron, etc.), and chlorine to use them in traditional or advanced filter stations, such reverse osmosis plants or ion exchange water filters. A glass tube was filled with KDF, sand and gravel layers and used as a multi-layer's filter, and tests were carried out on a water sample that has been prepared in the lab with concentration of 2 mg/l for heavy elements and 5 mg/l for chlorine. Flow rates of the tested water sample were 20, 40, 60, 80 and 100 l/hr. The results show a very high efficiency of such filters to remove of chlorine from the treated water by 90% and more, while the efficiency of the modified filter to remove lead, nickel and iron was 92%, 88%, and 67% respectively; however, there was no significant records in removing the biological contaminants.

Rationalization of water treatment as a top priority goal of sustainable development of residential areas and improvement of environmental quality

The problem of searching for resource-saving and cost-effective technologies for cleaning rinsing water within the filter structures of waterworks remains relevant for many years. Most of contaminated wastewater of Sverdlovsk Region comes to the surface water bodies from Municipal Unitary Enterprise ‘Vodokanal’. The solution of engineering tasks aimed at the environmental situation improvement in urban areas and water bodies protection from pollution subsequently requires continuous improvement of wastewater treatment methods. The paper examines the construction project of rinsing waters treatment unit of the filter station of Municipal Unitary Enterprise ‘Vodokanal’ with the formation of dehydrated sludge and provides the calculations of technical and economic parameters of the project. The project implementation is expected to result in a decrease of the man-caused environmental impact by eliminating the rinsing waters discharge, as well as by reducing the amount of water taken from the surface source into the technological process of potable water treatment.

Risk of man-made and ecological disasters at the filter stations in the Donetsk and Luhansk regions

The ecological situation in the territories of Donetsk and Luhansk regions in the context of the military conflict which began in early 2014 is unstable and requires a timely resolution. Military conflicts lead to a number of dangerous impacts on soils and landscapes, surface and underground waters, vegetation and fauna, and military actions significantly increase the risk of emergencies in industrial enterprises and infrastructural facilities. Conflicts occurring in industrially developed territories with a large number of environmentally hazardous enterprises and objects constitute a particular danger to the environment. This article considers critical infrastructural objects on the example of objects of water supply (filtering stations) of Donetsk and Luhansk regions. Damage to or destruction of these objects threatens national security, the economy, and the health and safety of the population. Water supply facilities require the attention and access of international experts for preventing man-made and ecological disasters. An expert evaluation was carried out to assess theenvironmental threats and risks, existing threats were identified, an information and analytical system was developed, and recommendations were issued for minimizing the risks of man-made and ecological disasters. The current risk of an industrial accident with significant environmental consequences occurring in the course of the conflict is in the range from "low" to "average". According to an expert assessment within the framework of the OSCE Project Coordinator's study in Ukraine, in the course of development of any adverse scenarios, the potential danger of emergencies with serious environmental consequences remains significant. With large volumes of liquid chlorine emissions into the air, the population living in the zone of possible chemical contamination can be subjected to a severe degree of poisoning, which will lead to lethal consequences and a large number of victims. Economic development of Donetsk and Lugansk regions without the obligatory consideration of environmental factors is impossible. Ensuring the rehabilitation of the ecology of Donetsk and Luhansk oblasts is an important factor in bringing environmental protection activities in the region into line with the requirements of environmental safety in the current social and economic conditions and making these activities an integral part of the sustainable economic and social development of Ukraine.

Role of Imaging in Diagnosis, Predicting Biological Activity and in Treatment Plan of Hydatid Disease

Cystic Echinococcosis (CE) is a zoonotic parasitic disease caused by the larval stage of the cestode Echinococcus granulosus. Hydatid cyst is a significant universal medical problem. In human cestode involves any organ and develops to hydatid cyst. Liver is the first and most frequently involved organ as the liver is the primary filter station of portal circulation. Though hydatid disease is benign disease, traditionally surgery is the treatment of choice for complete elimination of infective focus, which is associated with considerable mortality, morbidity. Systemic chemotherapy and percutaneous drainage have evolved in the recent past as an alternative to conventional surgery. The safety and success rate of these methods is influenced by the size, stage, location of the cysts and associated complications. Benzimidazoles can be considered in multiple, small hydatid cysts, but large cysts (cysts > 6 cm), bone marrow depression, pregnancy are contraindications of pharmacotherapy. Percutaneous drainage combined with ALB is a safe and effective treatment in liver hydatid patients with a surgical contraindication and younger cysts, but the presence of certain radiological signs (pericystic ducts and exophytic components) is a contraindication to non-surgical management because of the danger of biliary obstruction. However, the surgical treatment technique also cannot be standardized, should be tailored according to the cyst relation to the Broncho, biliary, vascular structures and associated complications if any. This review will focus on role of imaging in establishing the diagnosis, in determining cyst location, size, stage of the cyst and in identifying any associated complications, so that enable the clinician to perform recommended therapeutic procedures for the different cyst types and tailor the procedure performed based on cyst relation to broncho, biliary, vascular structures and associated complications.

HYDROCYCLONE EQUIPMENT FOR PREPARATION OF WATER FOR INJECTION INTO OIL-BEARING HORIZONS WITH THE AIM OF INCREASING OIL RECOVERY

For increasing the recovery of productive aquifers used for water flooding waters from surface sources, as well as oilfield wastewater generated in the oil fields in the extraction and primary processing of oil. To ensure long-term injectivity of injection wells through which water flooding of oil reservoirs need to be cleaned from surface water sources from suspended substances, oil field waste waters from petroleum products and mechanical impurities. At Kazan state University of architecture and construction (KSUAE) developed and implemented hydrocyclone installations for the preparation of water used for injection into productive horizons So in order to prepare water for use in the system of reservoir pressure maintenance, the installation is designed without the use of reagents, consisting of a hydrocyclone installation, pressure lamella settler and filter station. To clean oilfield wastewater is designed installations, the unit is a cyclone–settler, consisting of one or two batteries discharge dogproducts hydrocyclones and pressure tanks of various designs. Research KSUAE showed that the treatment of oilfield wastewater in the pressure dogproducts cylindrical hydrocyclones is not only the separation of suspensions and emulsions of the type «oil-in-water», but also destroyed membranes around oil droplets; their enlargement occurs (coalescence); there is an increase in the degree of: emulsions of this type. All this greatly intensifies the process of after–treatment of oilfield wastewater by sedimentation. The concentration of oil products in oil field waste waters after treatment in installations of the type “block hydrocyclone – sump” is reduced from 3000 to 50–60 mg/l, and the solids content is from 200 to 50 mg/l. One of the latest developments KSUAE is to install a type “a hydrocyclone unit – cylindrical chamber –sump”, consisting of battery pressure hydrocyclones design KSUAE, cylindrical containers of the upper and lower drains and horizontal pressure of the sump. Pressure hydrocyclones that are included with the installation of “block hydrocyclone – cylindrical chamber – sump”, work as hydrodynamic kaplonstudio. Fluid flows from the upper and lower drains hydrocyclones are received in the cylindrical chamber in the form of swirling jets, the energy of which is used for further hydrodynamic treatment of oilfield wastewater: in them there is the further consolidation of the oil droplets, which increases the efficiency of the separation of emulsions of the type “oil-in-water” method of settling. The concentration of oil in oilfield wastewater decreases from 3000 to 60 mg/l, and the content of mechanical impurities from 200 to 50 mg/l. These block hydroclone installations are introduced at the enterprises of “Tatneft”. To reduce the concentration in oilfield wastewater of petroleum products and mechanical impurities up to 10 mg/l after treatment in the installation type “block hydrocyclone– sump” or “block hydrocyclone – cylindrical chamber –sump” should be dispatched to post–treatment in the filtration system, consisting of rapid filters or filters very fast and accurate. Block hydrocyclone units have high power density, compact, fully automated, are blocks full of factory manufacturing; provide an opportunity to create an effective treatment technology of oilfield wastewater with the least material and energy costs.

The role of lymph node sinus macrophages in host defense

Strategically positioned along lymphatic vessels, lymph nodes act as filter stations preventing systemic pathogen dissemination; they are primary sites of innate immune responses and provide the staging grounds for the generation of adaptive immunity. Critical mediators of these lymph node functions are two phenotypically and functionally distinct subsets of macrophages: the subcapsular sinus macrophages and the medullary macrophages. This review focuses on the phenotype and function of these lymph node sinus-resident macrophages and summarizes methods for their proper identification and experimental manipulation.

Application of vacuum belt press filters for cane mud filtration and performance comparison with rotary filters

Bois-Rouge factory, an 8000 t/d cane Reunionese sugarcane mill, has fully equipped its filtration station with vacuum belt press filters since 2010, the first one being installed in 2009. The present study deals with this 3-year experience and discusses operating conditions, electricity consumption, performance and optimisation. The comparison with the more classical rotary drum vacuum filter station of Le Gol sugar mill highlights advantages of vacuum belt press filters: high filtration efficiency, low filter cake mass and sucrose content, low total solids content in filtrate and low power consumption. However, this technology needs a mud conditioning step and requires a large amount of water to improve mud quality, mixing of flocculant and washing of filter belts. The impact on the energy balance of the sugar mill is significant. At Bois-Rouge mill, studies are underway to reduce the water consumption by recycling low d.s. filtrate and by dry cleaning the filter belts.

The thalamus in cirrhotic patients with and without hepatic encephalopathy: A volumetric MRI study

Background & aimsThe thalamus is a major relay and filter station in the central neural system. Some previous studies have suggested that the thalamus maybe implicated in the pathogenesis of hepatic encephalopathy. The aim of our study was to investigate changing thalamic volumes in cirrhotic patients with and without hepatic encephalopathy. MethodsNeuropsychological tests and structural MR scanning were performed on 24 cirrhotic patients, 23 cirrhotic patients with minimal hepatic encephalopathy, 24 cirrhotic patients during their first episode of overt hepatic encephalopathy, and 33 healthy controls. Voxel-based morphometry analysis was performed to detect gray matter morphological changes. The thalamus and whole brain volume were extrapolated. A receiver operating characteristic curve analysis of thalamic volumes was used to discriminate patients with minimal hepatic encephalopathy from those with hepatic cirrhosis. ResultsThalamic volume increased in a stepwise manner in patients with progressively worse stages of hepatic encephalopathy compared to healthy subjects. Additionally, a comparison of gray matter morphometry between patients with Child–Pugh grades A, B, or C and controls revealed a progression in thalamic volumes in parallel with the degree of liver failure. Moreover, thalamic volume was significantly correlated with the number connection test A time and digit-symbol test score in cirrhotic patients with minimal hepatic encephalopathy (r=0.659, P=0.001; r=−0.577, P=0.004; respectively). The area under the receiver operating characteristic curve was 0.827 (P=0.001). ConclusionsA significantly increased thalamic volume may be provide an objective imaging measure for predicting seizures due to minimal hepatic encephalopathy in cirrhotic patients.

Оценка эффективности коагулянтов и флокулянтов при осветлении поверхностных вод

A comparative assessment of different agents for treatment of surface waters in the process of volume and contact coagulation has been performed. The volume coagulation at the “Mayak” filtering station, the town of Polevskoy, proved aluminum sulfate and aluminum-iron coagulant the most effective for water treatment during the flood period. To attain norm indicators of the purified water it is necessary to use flocculants and auxiliary agents. It is a good practice to use flocculating mixtures for contact coagulation.

Subcapsular sinus macrophages prevent lethal vesicular stomatitis virus (VSV) infection (43.11)

Abstract When a pathogen escapes innate host responses at the site of entry, it has the potential to spread systemically by accessing tissue-draining lymph vessels that channel interstitial fluid to the venous circulation. Before reaching the blood, the tissue-derived lymph must first pass through draining lymph nodes (LNs). LN act as filter stations preventing pathogens from reaching the systemic circulation and they are the staging grounds for adaptive immune responses, providing a specialized environment for the presentation of antigens to B and T cells. It is unclear how viruses are cleared from afferent lymph and how antiviral immune responses are generated. We have previously identified a population of CD11b+CD169+ macrophages on the floor of the subcapsular sinus (SCS) and in the medulla of LNs that capture viral particles within minutes after subcutaneous (sc) injection. Using VSV, an acutely cytopathic RNA virus closely related to rabies virus, we show here that these macrophages are critical to prevent viral access to nerve termini located in the SCS. Indeed, mice depleted of SCS macrophages develop an ascending CNS paralysis that leads to death in 50% of the animals 6-10 days after sc infection. Macrophage-depleted mice die despite mounting an increased neutralizing antibody (nAb) response. The notion that nAb are dispensable for protection against a sc infection (the natural route of transmission of this virus) is further demonstrated by the fact that antibody-deficient mice, which die upon intravenous infection, survive a sc VSV infection as long as SCS macrophages are present. While nAb are unnecessary for survival, B cells are required, and their protective role presumably relies on maintenance of LN architecture and normal macrophage phenotype.