Approaches and tools to manipulate the carbonate chemistry

Although the chemistry of ocean acidifi cation is very well understood (see chapter 1), its impact on marine organisms and ecosystems remains poorly known. The biological response to ocean acidifi cation is a recent field of research, the fi rst purposeful experiments have only been carried out as late as the 1980s (Agegian, 1985) and most were not performed until the late 1990s. The potentially dire consequences of ocean acidifi cation have attracted the interest of scientists and students with a limited knowledge of the carbonate chemistry and its experimental manipulation. Perturbation experiments are one of the key approaches used to investigate the biological response to elevated p(CO2). Such experiments are based on measurements of physiological or metabolic processes in organisms and communities exposed to seawater with normal and altered carbonate chemistry. The basics of the carbonate chemistry must be understood to perform meaningful CO2 perturbation experiments (see chapter 1). Briefl y, the marine carbonate system considers € CO2 ∗(aq) [the sum of CO2 and H2CO3], € HCO3 −, € CO3 2−, H+, € OH− , and several weak acid-base systems of which borate-boric acid (€ B(OH)4 − , B(OH)3) is the most important. As discussed by Dickson (chapter 1), if two components of the carbonate chemistry are known, all the other components can be calculated for seawater with typical nutrient concentrations at given temperature, salinity, and pressure. One of the possible pairs is of particular interest because both components can be measured with precision, accuracy, and are conservative in the sense that their concentrations do not change with temperature or pressure. Dissolved inorganic carbon (DIC) is the sum of all dissolved inorganic carbon species while total alkalinity (AT) equals € [HCO3 − ] + 2 € [CO3 2− ] + € [B(OH)4 − ] + € [OH− ] - [H+] + minor components, and refl ects the excess of proton acceptors over proton donors with respect to a zero level of protons (see chapter 1 for a detailed defi nition). AT is determined by the titration of seawater with a strong acid and thus can also be regarded as a measure of the buffering capacity. Any changes in any single component of the carbonate system will lead to changes in several, if not all, other components. In other words, it is not possible to vary a single component of the carbonate system while keeping all other components constant. This interdependency in the carbonate system is important to consider when performing CO2 perturbation experiments. To adjust seawater to different p(CO2) levels, the carbonate system can be manipulated in various ways that usually involve changes in AT or DIC. The goal of this chapter is (1) to examine the benefi ts and drawbacks of various manipulation methods used to date and (2) to provide a simple software package to assist the design of perturbation experiments

The \u3ci\u3ePanuwat\u3ci\u3e Snowball: Correlation Does Not Equal Materiality

Insider trading is a term of art referencing the fraudulent practice of trading securities in a company on the basis of material, nonpublic information about that same company in breach of some duty owed to another. The practice erodes the public’s trust in the integrity of our capital markets for a reason that is rather intuitive: it is inherently unfair to allow an individual to make a quick and certain profit by exploiting material, nonpublic information to which he privy due solely to his position in a company or some other relationship of trust and confidence. In this context, unrelenting civil enforcement by the Securities and Exchange Commission (“SEC”) is surely warranted. But, what if an individual in possession of material, nonpublic information about one company trades in the securities of a different company? Is a civil enforcement action warranted in this context? This question is derived from the novel “shadow trading” theory of insider trading liability proffered by the SEC in its August 2021 civil enforcement action against Matthew Panuwat. Judicial endorsement of the SEC’s shadow trading theory presents concerning doctrinal and practical implications. First, it upends the traditional materiality inquiry required in an insider trading action. Second, it transforms Rule 10b-5—the SEC’s primary enforcement mechanism—into a rule without limitation. Third, it will increase the cost of executing securities transactions as investors in possession of material, nonpublic information about one company could be required to abstain from trading in an endless list of companies, industries, and investment vehicles. Taken together, these considerations compel the rejection of the SEC’s shadow trading theory of insider trading liability

Estandarización micrográfica de especies de Baccharis L. (Asteraceae)

Controversies still exist regarding the differentiation of some Baccharis sect. Caulopterae species known as “carqueja”. In the present work we studied anatomically five of these species: Baccharis articulata (Ba), Baccharis crispa (Bc), Baccharis gaudichaudiana (Bg), Baccharis microcephala (Bm) and Baccharis trimera (Bt). Ba and Bc are considered official in Argentinean Pharmacopeia and Bt in the Brazilian Pharmacopeia. Bg and Bm are considering possible substitutes. The qualitative and quantitative variables for each one were determined, emphasizing the importance of anatomic characters as taxonomically useful. Analytical micrographs of the studied species were elaborated as reference standards for quality control of the raw drug.Aún existen controversias con respecto a la correcta diferenciación de las especies de Baccharis de la sección Caulopterae conocidas como “carqueja”. En este trabajo se estudió anatómicamente a cinco de estas especies: Baccharis articulata (Ba), Baccharis crispa (Bc), Baccharis gaudichaudiana (Bg), Baccharis microcephala (Bm) y Baccharis trimera (Bt). Las especies Ba y Bc son consideradas oficiales en la Farmacopea Argentina y Bt en la Farmacopea Brasileña. Bg y Bm son consideradas posibles sustituyentes de las anteriores. Se determinaron las variables cualitativas y cuantitativas para cada una, resaltando la importancia de la anatomía en la obtención de caracteres taxonómicos para poder diferenciarlas. Con los datos obtenidos se elaboraron las micrografias analíticas de las especies estudiadas, para que puedan ser utilizadas como patrones de referencia para el control de calidad de la droga cruda.Fil: Rodriguez, María Victoria. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gattuso, Susana Julia. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; ArgentinaFil: Gattuso, Martha Ana. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; Argentin

Problem Solving Strategies: Helping Students Develop a Conceptual Understanding of Word Problems

Over the past few years, teachers have seen a decline in students\u27 mathematical understanding due to a shift from procedural to conceptual knowledge (Griffin & Jitendra, 2008). Many students struggle with comprehending word problems due to being taught strategies that do not emphasize reading comprehension. Various problem solving strategies have been created to help students gain a conceptual understanding of word problems. This study examined three different strategies in order to examine the effects it has on students\u27 understanding of word problems. Students were taught the Reciprocal Teaching Strategy, Schema Based Instruction Strategy, and Visual Strategies. These strategies used different methods to help students understand word problems. This study used both qualitative and quantitative methods to examine students\u27 understanding of word problems using these three strategies. Results show that the problem solving strategies helped students to gain a better understanding of word problems but did not affect how students verbally explained how they solved the word problems

Comments: The Bankruptcy Reform Act of 1978: Dischargeability of Obligations Incurred under Property Settlements, Separation Agreements, and Divorce Decrees

It is the underlying policy of the Bankruptcy Act to give the bankrupt a fresh start and to relieve him of pre-existing debts. In many instances the determination of what is alimony, [maintenance, and support] comes into direct conflict with this policy. Under the Act these debts are nondischargeable. Thus, in an attempt to construe the Act narrowly and uphold the underlying policy of fresh start, courts are faced with the problem of determining how to characterize marital obligations

Common Issues of Compliance with Personal Protective Equipment for Construction Workers

Personal Protective Equipment (PPE) is an essential component to the safety of workers on construction jobsites. Construction is ranked one of the most dangerous industries to work in, with the highest reports of fatal work injuries. For this reason, it is required that construction employees wear PPE to keep them safe during work. Despite this requirement, many workers neglect to wear PPE, exposing themselves to high risk of injury and death. A survey was conducted on thirty-three (33) construction workers in California to gain a better understanding of issues with PPE and reasons for non-compliance. The survey found that only 64% of construction workers always wear their PPE. Analysis of this survey provided the highest ranked reasons for non-compliance from a worker’s perspective including it causes stress in hot, sunny, confined, or poorly ventilated areas, it is not necessary at all times, and it is uncomfortable. Other reasons such as anxiety and fit of PPE were also brought to light. This paper will review the dangers of working in the construction industry, provide insight from a worker’s perspective on reasons for non-compliance with PPE, and pose solutions for this ongoing problem

Laser perforation for computer paper

In today\u27s computer paper printing, cross and edge perforations are done only by mechanical perforators. The mechanical perforation process works fine since the width of the bridges and the length of the holes to be perforated remain large. Concerned with improvements in quality, printers have introduced microperforations. The holes and bridges of the perforation pattern are so small that after the user has torn off the sheet of computer paper along the perforation pattern, the edges of the document are very smooth and clean. Unfortunately, microperforations are reaching the limits of what can be achieved by the mechanical perforators. Because of the physical contact between the perforating tool and the paper, the perforation pattern is damaged. The tensile strength of the microperforation pattern decreases significantly and the paper often jams in the computer printers. Mechanical perforator dies wear and may even break.Therefore, holes are incompletely perforated or missing, so that the document is likely to be damaged when it is torn off along the perforation pattern by the user. Incomplete or missing perforations increases the tensile strength of the perforation pattern. Therefore, the printer can increase the quality of a perforation pattern by reducing its variability in tensile strength. This thesis studies the perforation of computer paper by laser beam. It is demonstrated through a microscopic study that laser perforations are free of all the defects which are inherent to the mechanical perforation process. It has been found that laser perforated holes remain open while mechanically perforated holes close back just after being perforated. The tests which have been carried out show that using a laser instead of a mechanical perforator to do microperforations reduces the variability in the tensile strength from 0.694 kilograms to 0.0751 kilograms. This improvement is significant. However, using a laser instead of a mechanical perforator to do large-size perforations reduces the variability in tensile strength only from 0.0421 kilograms to 0.0338 kilograms. This improvement is not significant. A mathematical model expressing the relationship between the tensile strength of a perforation pattern, the width of the bridges, and the number of bridges per inch has been established. The correlation found between the model and the experimental values is high (r = 0.98). This mathematical model is a simple method which allows the printer to adjust the tensile strength of a laser perforation pattern to the desired value. This model requires only simple calculations, and the knowledge of one basic characteristic - the tensile strength of the paper. As a conclusion, the laser beam is a very valuable tool which can achieve very high quality microperforations on computer paper. However, it seems not worth using a laser to do large-size perforations on computer paper since the decrease in tensile strength variability over the mechanical perforation process is not significant. The fact that laser perforated holes remain wide open could improve high speed folding and piling in the press deliveries by allowing the air trapped between the sheets of computer paper to escape through the perforated holes. This property has also already found an interesting application for cigarette filter paper

Single-center experience in the treatment of visceral artery aneurysms

Background: Visceral artery aneurysms (VAAs), although rare, represent a life-threatening disease with high mortality rates. With the more frequent use of diagnostic tests, there has been an incidental detection of these lesions which are mostly asymptomatic. It follows that surgeons are increasingly called to decide on the most appropriate management of VAAs between an open surgical or endovascular approach and among the different endovascular options currently available. The aim of this retrospective study was to evaluate the results of open surgery and interventional endovascular strategies of visceral artery aneurysms with respect to technical success, therapy-associated complications, and postinterventional follow-up in the elective and emergency situation. Methods: From January 1992 to January 2017, 125 open surgical or endovascular interventions for VAA were performed at our institution. Once the VAA was diagnosed and the indication for treatment was assessed, the preoperative diagnostic work-up consisted of contrast computed tomography (CT) or magnetic resonance imaging (MRI) and, in some patients, digital subtraction angiography. Follow-up included clinical and duplex ultrasound scan (DUS) and contrast-enhanced ultrasound to assess the treated vessel patency and organ perfusion after 1, 6, and 12 months, and yearly thereafter. CT or MRI controls were also performed at 1 year of follow-up and only when DUS was not diagnostic or showed a complication thereafter. After the first 5 years of follow-up, the status of the patient was obtained by a structured telephone survey. Results: The treatment option was endovascular in 56 of 125 cases (44.8%). Technical success was 98.3%. In one case, the procedure was interrupted for the extensive dissection of the afferent vessel. Twenty-six patients were treated by coil embolization while 29 with covered stenting. The endovascular approach was in emergency in two cases (3.6%). In the endovascular group, mortality was nil. Complications occurred in 5 cases (8.9%): 1 subacute intestinal ischemia caused by superior mesenteric artery dissection, 2 aneurysm reperfusion, 1 stent thrombosis, and 1 massive splenic hematoma. In 69 (55.2%) cases, surgical treatment was preferred, with 24 VAA resections and 45 arterial reconstructions. In 20 cases (29%), open surgery was performed in emergency conditions. In the surgical group, 8 emergency patients (40%) died intraoperatively. The mortality after elective surgical interventions was nil. Complications after surgery were 4 graft late thrombosis (5.8%): asymptomatic in three cases and requiring splenectomy in one. Conclusions: There is no overall consensus regarding the indications for treatment of VAA. Currently in emergent setting, the endovascular approach should be considered as the first choice because of its reduced invasiveness, faster way to access and bleeding control; this accounts for the lower morality of the interventional therapy than open surgery. Endovascular approach is effective for elective repair of VAAs, but procedure-related complications may occur in a not negligible number of patients. Given comparable mortality rates and low procedure-related complication rate, surgical approach still has space in the elective management of VAAs, especially for aneurysms unsuitable or challenging for the endovascular option in patients with low surgical risk. The size, location, and morphology of VAAs, systemic or local comorbidities, and specific anatomical situations such as previous abdominal surgery should dictate treatment choice

A Tool for Railway Transport Cost Evaluation

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Idiopathic Proximal Hemimegacolon in an Adult Woman

Idiopathic proximal hemimegacolon is a disorder characterized by bowel dilatation proximal to the splenic flexure. It is a very rare and therefore a poorly understood clinical entity. This report describes a case of idiopathic proximal hemimegacolon in a 44-year-old woman. The patient suffered from 2 episodes of constipation and bowel dilatation over 4 years and was successfully treated by medical therapy