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Constraints of the underwater environment pose certain challenges to the design of routing protocols for underwater sensor networks. One such constraint is free mobility of sensor nodes with water currents. Free mobility and asymmetric acoustic propagation characteristics may lead to network partitioning which results in one or more nodes being unable to connect to the rest of the network and thus unable to report their sensed data. In this work, we propose a two-stage routing protocol to enable not only the connected nodes but also the partitioned nodes to successfully report their data thus improving the overall packet delivery ratio. We also introduce a minimum energy threshold and a rerouting scheme to delay death of busier nodes, thereby ensuring that nodes stay alive longer for their sensing job, and to avoid connectivity holes, respectively. Moreover, we also resolve forwarding loops to avoid the unnecessary waste of resources. Our results show that the proposed scheme successfully resolves network partitions and achieves a higher packet delivery ratio while avoiding early death of sensor nodes.

Underwater Sensor Networks (UWSN) have attracted huge attention due to their significance in oceanic observation and exploration. They offer a vast number of applications, many of which require routing the sensed data to a centralized location. This makes routing an important part of the design of such applications. In this paper, we present a comprehensive survey of recently proposed routing protocols for UWSNs. We evaluate the proposed schemes through an extensive set of parameters that define the core characteristics of a routing protocol. Moreover, we present a summary of the methods used by each scheme to familiarize readers with the basic operations of the schemes. We also present our view of the strengths and weakness of each scheme. For ease of description, the addressed routing protocols are divided into two categories: localization-based, and localization-free routing schemes. Each of the two categories is further divided into the protocols that consider node mobility, and those that do not. Lastly, we present our view on open research topics.

Knowledge about the geographic coordinates of underwater sensor nodes is of primary importance for many applications and protocols of under water sensor networks (UWSNs) thus making localization of sensor nodes a crucial part of underwater network design. In case of mobile underwater sensor network, location estimation becomes challenging not only due to the need for periodic tracking of nodes, but also due to network partitioning caused by the pseudo-random mobility of nodes. Our proposed technique accomplishes the task of localization in two stages: (1) relative localization of sensor nodes with respect to a reference node at regular intervals during sensing operation. (2) Offline absolute localization of sensor nodes using absolute coordinates of the reference node and relative locations estimated during stage 1. As our protocol deals with mobile underwater sensor networks that may introduce network partitioning, we also propose a partition handling routine to deal with network partitions to achieve high localization coverage. The major design goal of our work is to maximize localization coverage while keeping communication overhead minimum, thus achieving better energy efficiency. Major contributions of this paper are: (1) Two energy efficient relative localization techniques, and (2) A partition handling strategy that ensures localization of partitioned nodes.

Many applications of underwater sensor networks (UWSNs), such as target tracking, reconnaissance and surveillance, and marine life monitoring require information about the geographic locations of the sensed data. This makes the localization of sensor nodes a crucial part of such underwater sensing missions. In the case of mobile UWSNs, the problem becomes challenging, not only due to a need for the periodic tracking of nodes, but also due to network partitioning as a result of the pseudo-random mobility of nodes. In this work, we propose an energy efficient solution for localizing nodes in partitioned networks. Energy consumption is minimized by clustering unlocalized partitioned nodes and allowing only clusterheads to carry out a major part of the localization procedure on behalf of the whole cluster. Moreover, we introduce a retransmission control scheme that reduces energy consumption by controlling unnecessary transmission. The major design goal of our work is to maximize localization coverage while keeping communication overheads at a minimum, thus achieving better energy efficiency. The major contributions of this paper include a clustering technique for localizing partitioned nodes and a retransmission control strategy that reduces unnecessary transmissions.

Steel is the most important structural material for humankind which is used in every sphere of daily life as well as in the industrialized world. Being a ubiquitous material, it gained importance over years and regarded as irreplaceable until now. For its abundance in nature, ease of fabrication, numerous engineering properties upon processing, easy availability and low cost have made it a prime material to be used for several engineering applications. For different purposes and needs, steel has been modified from past eras and thus plain carbon steel was invented over years, giving us a scope to use it for different purposes. A major portion of the daily day tools, drivers along with other applications in engineering structures, designs, and various products manufacturing are now made possible because of the invention of plain carbon steel. Here the classification of plain carbon steel has been given with proper definition along with its development history. Designation system and composition have also been discussed to know the system behind the naming of plain carbon steel in today’s world and to have a normal compositional range of it. Moreover, relevance with a phase diagram has also been given to get acquainted with the evolution of microstructures, phases, and microconstituents, at different typical compositions. At the end, description of different plain carbon steels has been shown with necessary features along with a wider range of mechanical properties and applications in order to have a comprehensive knowledge of this versatile metallic material.

Vitamin D deficiency (25(OH)D < 20 ng/mL) is likely to be present in about 40% of veterans and is associated with much higher health care costs and service use. The prevalence of vitamin D deficiency is likely to be higher in certain subgroups such as ethnic minorities, those who are chronically ill, and nursing home residents. The lack of adequate sunlight exposure and poor dietary intake are common contributors to this deficient state. Moreover, vitamin D deficiency has also been noted in individuals taking vitamin D supplements within the recommended daily intake. To achieve a 25(OH)D value in the normal range (30-100 ng/mL), many studies indicate a much higher daily oral intake than currently recommended is needed. Inadequate vitamin D dosing may account for failure of some studies to show a benefit. Testing for vitamin D insufficiency levels remains suboptimal and serial monitoring in veterans to assess if a vitamin D-replete state has been achieved also remains less than adequate. The lack of evidence-based guidelines for testing and monitoring has hampered optimal management of this very common condition. The cardiovascular, immunologic, anti-infective, and oncologic benefits of a vitamin D-replete state are becoming recognized. Achieving a vitamin D-replete state may prolong longevity. Achieving adequate vitamin D status in US veterans is an important health measure that should be undertaken.

The aim of the study was to compare symptom-triggered and standard benzodiazepine regimens for the treatment of alcohol withdrawal syndrome in an emergency department clinical decision unit. The authors found that the symptom-triggered approach reduced cumulative benzodiazepine dose and length of stay.

Hepatosplenic T-cell non-Hodgkin's lymphoma (HSTCL) is a rare, aggressive form of NHL, with a median survival of approximately 8 months. We were able to successfully induce complete remission in a patient with alpha/beta HSTCL who was refractory to multiple prior chemotherapy regimens, using the humanized anti-CD52 monoclonal antibody alemtuzumab (Campath). Once disease was controlled, the patient was able to undergo allogeneic stem cell transplantation (SCT), which resulted in complete remission. Furthermore, upon relapse, we were able to re-induce complete clinical and molecular remission with donor lymphocyte infusions. At Day 655 (post-SCT), the patient remains in complete remission. These data suggest a potential role for alemtuzumab and allogeneic SCT in the treatment of T-cell NHL.

Several trials have shown the activity of thalidomide (THAL) in relapsed multiple myeloma (MM) patients failing PBSCT or conventional chemotherapy. PBSCT is considered standard treatment for most patients requiring therapy for MM; however, patients with VAD-resistant disease may not be able to receive PBSCT due to rapidly advancing disease. We report four cases of VAD-refractory MM salvaged with THAL + VAD followed by PBSCT. All patients underwent stem cell mobilization with cyclophosphamide (Cy) (4.5 g/m(2)) and GMCSF. Melphalan (140-200 mg/m(2)) was given as conditioning. All patients engrafted within 12-16 days after PBSCT. Day +100 evaluation showed the following: very good partial response (n = 1) and complete response (n = 3). After a median follow-up to 153 days, two patients continue to take THAL with no signs of disease progression. One patient developed CHF and was taken off THAL while another patient has died of progressive disease while on THAL (MTD 50 mg). In conclusion, VAD-refractory patients were salvaged with the addition of THAL to VAD. They were subsequently able to undergo autologous PBSCT for MM, which will likely improve their overall survival. This suggests that THAL and other related immunomodulatory drugs may prove useful for initial MM therapy in combination with standard chemotherapy followed by PBSCT.