glass transition raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2025-09-15 and is reviewed periodically as new material appears.
Stability of a lyophilized product depends on its glass transition temperature, the temperature at which the amorphous cake transitions from a glassy to a rubbery state. Storage below this temperature minimizes molecular mobility and slows chemical degradation. If the storage temperature exceeds the glass transition temperature, the cake may collapse, shrink, or become sticky. Accelerated stability studies at elevated temperatures and humidity help predict shelf life, but they do not always reflect real-time behavior. Residual moisture content also plays a critical role in long-term stability.
Reconstitution involves adding a suitable diluent, often sterile water or a buffer, to the dried cake. Gentle swirling or inversion helps dissolve the material without creating excessive foam. The time required for complete dissolution can range from seconds to several minutes and depends on the cake structure and the diluent. Improper reconstitution, such as vigorous shaking or using the wrong diluent, can cause protein aggregation or loss of activity. After reconstitution, the product may have a limited shelf life and should be used according to its labeling.
Secondary drying removes bound water that remains after ice sublimation. Shelf temperature is raised gradually while pressure remains low, reducing water content to a target range. Over-drying can cause brittleness or electrostatic issues, while under-drying affects stability. The endpoint is often judged by pressure rise tests, temperature measurements, or water content analysis. Scale-up depends on matching heat and mass transfer across equipment sizes. Small changes in shelf temperature or pressure can alter cycle length substantially.
Lyophilization, or freeze-drying, removes water from a material by freezing it and then lowering pressure so ice changes directly to vapor. The process relies on sublimation, the phase transition from solid to gas without an intervening liquid state. It is used for heat-sensitive materials that would degrade in conventional drying. The three stages are freezing, primary drying, and secondary drying, each with distinct temperature and pressure requirements. In practice, cycle design balances these variables.
Freezing determines ice crystal structure and pore size, which affect drying speed and product uniformity. Rapid freezing creates small crystals, while slow freezing creates larger crystals and often faster sublimation. During primary drying, chamber pressure is held below the vapor pressure of ice, and shelf temperature supplies heat for sublimation. The ice front recedes, leaving a porous matrix. Thermal limits such as collapse and eutectic temperatures set safe boundaries for formulation. These limits vary with solute composition and concentration.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white porous cake | Color depends on formulation. |
| Typical storage temperature | 2–8 °C | Refrigerated for many biologics. |
| Residual moisture | <1% to 3% | Low moisture improves stability. |
| Container | Sealed glass vial | Often with rubber stopper and aluminum crimp. |
| Reconstitution time | Seconds to minutes | Varies with cake density and diluent. |
Analytical methods for lyophilized materials include X-ray diffraction for crystallinity, differential scanning calorimetry for thermal transitions, and scanning electron microscopy for pore morphology. Moisture sorption analysis shows how the cake responds to humidity. These methods help distinguish amorphous from crystalline states and detect phase changes. Open questions remain about how pore structure changes during long-term storage and how best to predict collapse under varied conditions. Comparisons across studies are complicated by differences in formulation, cycle, and storage history.
Quality control for lyophilized products focuses on appearance, moisture level, reconstitution time, and structural integrity. A cake should be uniform, intact, and free of meltback or collapse. Moisture level is measured by Karl Fischer titration or thermogravimetric analysis. Reconstitution time reflects pore structure and formulation. Visual inspection and vial integrity checks detect cracks, stopper defects, or particulate matter. These checks are often performed on samples from each batch. They help confirm that the drying cycle performed as intended.
The physics of freeze-drying couples heat transfer, mass transfer, and phase change. Heat supplied through the shelf must reach the sublimation front without melting the ice or degrading the product. Water vapor then travels through the already dried layer and leaves the chamber, where low pressure and cold traps keep it from returning. The dried layer acts as a resistance to vapor flow, so drying rate changes as the front recedes. Open questions remain about how pore structure and formulation heterogeneity affect drying uniformity at larger scales.
Lyophilization removes water from a frozen material by sublimation under reduced pressure. The process begins with freezing, which converts liquid water into ice and concentrates dissolved solids. Primary drying then lowers chamber pressure so ice changes directly into vapor without passing through a liquid phase. Secondary drying raises the shelf temperature to remove bound water that remains after ice sublimation. The result is a dry, porous structure that can be reconstituted later.
Formulation composition influences whether freeze-drying produces an intact cake or a collapsed mass. Excipients such as sugars and polymers can raise the collapse temperature and provide bulk during drying. The critical temperature for primary drying is often the collapse temperature or the glass transition temperature of the maximally concentrated phase. If the product temperature exceeds this threshold, the frozen matrix may soften and lose structure. Established practice therefore links shelf temperature and chamber pressure to the formulation's thermal properties.
Respiratory, allergic, or immune effects in infants or children are associated with man-made VOCs and other indoor or outdoor air pollutants. Some VOCs, such as styrene and limonene, can react with nitrogen oxides or with ozone to produce new oxidation products and secondary aerosols, which can cause sensory irritation symptoms. VOCs contribute to the formation of tropospheric ozone and smog. Health effects include eye, nose, and throat irritation; headaches, loss of coordination, nausea, hearing disorders and damage to the liver, kidney, and central nervous system. Some VOCs are suspected or known to cause cancer in humans. Key signs or symptoms associated with exposure to VOCs include conjunctival irritation, nose and throat discomfort, headache, allergic skin reaction, dyspnea, declines in serum cholinesterase levels, nausea, vomiting, nose bleeding, fatigue, dizziness. The ability of organic chemicals to cause health effects varies greatly from those that are highly toxic to those with no known health effects. As with other pollutants, the extent and nature of the health effect will depend on many factors including level of exposure and length of time exposed. Eye and respiratory tract irritation, headaches, dizziness, visual disorders, and memory impairment are among the immediate symptoms that some people have experienced soon after exposure to some organics. At present, not much is known about what health effects occur from the levels of organics usually found in homes.
The charge alleges that Viñas Alonso attempted to exchange $100 on the black market, and came after a tip-off by an anonymous informant. Advocates of Viñas Alonso said that if he had exchanged that money, he only intended to use it to buy food and supplies for the Llansó retirement home, which was again facing a food shortage. Viñas Alonso later wrote on Facebook that the money, which had agreed to be converted by a unanimous vote of the Board of Trustees at the Llansó retirement home, was made an at unofficial exchange rate of $MN378 for US$100, instead of the government-mandated exchange rate of $MN120. He said that there had been two such occasions of unofficial market exchange, and technically that does constitute an economic crime in Cuba, but that people are rarely prosecuted for such a low sum of money. He was then issued a work-from-home order, and restricted from leaving Cuba.
In plants, injuries result from the consumption of plant parts by herbivorous animals, including insects and mammals, from damage to tissues by plant pathogens such as bacteria and fungi, which may gain entry after herbivore damage or in other ways, and from abiotic factors such as heat, freezing, flooding, lightning, and pollutants such as ozone. Plants respond to injury by signalling that damage has occurred, secreting materials that seal off the damaged area, producing antimicrobial chemicals, and, in woody plants, regrowing over wounds.
==== Adverse effects ==== The most commonly reported adverse effects of nabiximol is dizziness, followed by drownsiness, fatigue, and nausea. Other adverse effects include anorexia, constipation, diarrhea, dysgeusia (taste disorder), oral ulcer, staining of tooth, upper abdominal pain, vomiting, xerostomia (dry mouth), confusion, and disorientation.
== Symptoms and signs == NAION typically presents suddenly upon awakening. The affected person notes seeing poorly in one eye. Vision in that eye is obscured by a dark shadow, often involving just the upper or lower half of vision, usually the area closer to the nose. There is no pain. Within approximately six months following the infarct, visual acuity improves by three or more lines of vision on the Snellen Chart (the chart with smaller letters on each lower line) in 42.7% of patients, while in 12.4% of patients, vision worsens by three lines. Opposite eye involvement occurs in approximately 15% to 20% of patients with NAION within 5 years. It is not always devastating as visual acuity may remain only moderately impaired. Furthermore, most cases of NAION involve the loss of a hemifield (either the upper or lower half of the visual field, but not both). A few cases of NAION involve near-total loss of vision.
Sources: en.wikipedia.org
Bipolar cell A type of amacrine cell that transmits signals from photoreceptors (rods and cones) to ganglion cells in the eye, playing a key role in visual processing. Bipolar disorder A mood disorder characterized by alternating episodes of depression and mania, associated with dysregulation in neurotransmitter systems and structural brain changes. Blood–brain barrier (BBB) A selective barrier formed by endothelial cells lining brain capillaries that restricts the passage of substances from the bloodstream into the central nervous system, protecting the brain from pathogens and toxins. Bouton Also known as an axon terminal or synaptic bouton, this is the swollen end of an axon where neurotransmitters are released into the synaptic cleft. Brain The central organ of the nervous system, responsible for processing sensory information, regulating bodily functions, and enabling thought, emotion, memory, and consciousness. Brain-derived neurotrophic factor (BDNF) A protein that supports the survival of existing neurons and encourages the growth and differentiation of new neurons and synapses. It is crucial for long-term memory and synaptic plasticity. Brain plasticity Also called neuroplasticity, this refers to the brain’s ability to reorganize and adapt by forming new neural connections throughout life, especially after injury or in response to learning and experience. Brainstem The posterior part of the brain that connects the cerebrum with the spinal cord.
Anhalt is now part of the state of Saxony-Anhalt. Baden is now part of Baden-Württemberg. Braunschweig is now part of Lower Saxony. Lippe is now part of North Rhine-Westphalia. Lübeck is now part of Schleswig-Holstein. Mecklenburg-Schwerin and Mecklenburg-Strelitz are now parts of Mecklenburg-Vorpommern. Oldenburg is now part of Lower Saxony, with its former exclaves now belonging to their neighbouring states of Rhineland-Palatinate and Schleswig-Holstein. Prussia was divided among the states of Berlin, Brandenburg, Lower Saxony, North Rhine-Westphalia, Rhineland-Palatinate, Saxony-Anhalt and Schleswig-Holstein. The erstwhile Prussian provinces of Brandenburg, Saxony, Schleswig-Holstein and Hanover formed the core of the states of Brandenburg, Saxony-Anhalt, Schleswig-Holstein and Lower Saxony, respectively. The Prussian provinces of Westphalia and Rhineland contributed most territory to the state of North Rhine-Westphalia, and Rhineland province contributed about half of the territory of the state of Rhineland Palatinate. Most of the Prussian province of Hesse-Nassau was merged with the existing state of Hesse. Some territories bordering other states were annexed to the bordering state. Also, Prussia had exclaves that were surrounded by other states. These became part of their surrounding states. All states, except Bavaria, now have territory of the former Free State of Prussia. Other former Prussian territories lying east of the rivers Neisse and Oder were lost in 1945 and are now part of Poland or Russia.
Irregular menstrual pattern: irregular bleeding and spotting is common in the first three to six months of use. After that time periods become shorter and lighter, and 20% of women stop having periods after one year of use. The average user reports 16 days of bleeding or spotting in the first month of use, but this diminishes to about four days at 12 months. Cramping and pain: many women feel discomfort or pain during and immediately after insertion. Some women may have cramping for the first 1–2 weeks after insertion. Expulsion: Sometimes the IUD can slip out of the uterus. This is termed expulsion. Around 5% of IUD users experience expulsion. If this happens a woman is not protected from pregnancy. Expulsion is more common in younger women, women who have not had children, and when an IUD is inserted immediately after childbirth or abortion. Perforation: Very rarely, the IUD can be pushed through the wall of the uterus during insertion. Risk of perforation is mostly determined by the skill of the practitioner performing the insertion. For experienced medical practitioners, the risk of perforation is one per 1,000 insertions or less. With postpartum insertions, perforation of the uterus is more likely to occur when uterine involution is incomplete; involution usually completes by 4–6 weeks postpartum. Special considerations apply to women who plan to breastfeed. If perforation does occur it can damage the internal organs, and in some cases surgery is needed to remove the IUD.
Check valves are often used with some types of pumps. Piston-driven and diaphragm pumps such as metering pumps and pumps for chromatography commonly use inlet and outlet ball check valves. These valves often look like small cylinders attached to the pump head on the inlet and outlet lines. Many similar pump-like mechanisms for moving volumes of fluids around use check valves such as ball check valves. The feed pumps or injectors which supply water to steam boilers are fitted with check valves to prevent back-flow. Check valves are also used in the pumps that supply water to water slides. The water to the slide flows through a pipe which doubles as the tower holding the steps to the slide. When the facility with the slide closes for the night, the check valve stops the flow of water through the pipe; when the facility reopens for the next day, the valve is opened and the flow restarts, making the slide ready for use again.
== IGF-binding proteins == IGF-1 and IGF-2 are regulated by a family of proteins known as the IGF-binding proteins. These proteins help to modulate IGF action in complex ways that involve both inhibiting IGF action by preventing binding to the IGF-1 receptor as well as promoting IGF action possibly through aiding in delivery to the receptor and increasing IGF half-life. Currently, there are seven characterized IGF Binding Proteins (IGFBP1 to IGFBP7). There is currently significant data suggesting that IGFBPs play important roles in addition to their ability to regulate IGFs. IGF-1 and IGFBP-3 are GH dependent, whereas IGFBP-1 is insulin regulated. IGFBP-1 production from the liver is significantly elevated during insulinopenia while serum levels of bioactive IGF-1 is increased by insulin.
Sources: en.wikipedia.org
LSD, a classical psychedelic, is deemed physiologically safe at standard doses (50–200 μg), and its primary risks lie in psychological effects rather than physiological harm. A 2010 study by David Nutt ranked LSD as significantly less harmful than alcohol, placing it near the bottom of a list assessing the harm of 20 drugs.
== History == Antibody Solutions was founded in 1995 by current president, John Kenney, PhD, Judith Lynch-Kenney, and Dennis and Bette Gould. Dr. Kenney previously managed the monoclonal antibody (MAb) development laboratory for Syntex Research (Roche) in Palo Alto, while Gould managed the MAb production facility for Syva Diagnostics. Gould left Antibody Solutions in 1997, eventually becoming a vice president for Sepragen Corporation. Kenney and Gould were assisted in the startup of the company by Barry Bredt, who had the foresight to acquire the domain name, www.antibody.com, for the company. Bredt later became director of the University of California at San Francisco’s General Clinical Research Center, and was a pioneer of the HIV/AIDS Diagnostics EasyCD4; he died on April 8, 2007. Antibody Solutions was incorporated in 1998 with Dr. Kenney as president and Judith Lynch-Kenney as chief financial officer. One of the first independent antibody discovery companies, the firm focused on custom antibody discovery for therapeutics, diagnostics and critical reagents. The company pioneered the use of bioreactors in antibody research by becoming the first CRO to produce antibodies in CELLine flasks in 2000. From 2004 to 2011, Antibody Solutions was headquartered in Mountain View, a short distance from Shoreline Park, Moffett Field and the Googleplex. In 2011, the company moved to new facilities in Sunnyvale. It moved to its current 33,300-square-foot location at 3033 Scott Blvd. in Santa Clara near the San Tomas Expressway in mid-2019. A grand opening for the Scott Blvd.
However, the clearance of benzodiazepines metabolized by glucuronidation (e.g., lorazepam; oxazepam, which is coincidentally a metabolite of diazepam; temazepam) are not affected by fluvoxamine and may be safely taken alongside fluvoxamine should concurrent treatment with a benzodiazepine be necessary. Additionally, it appears that benzodiazepines metabolized by nitro-reduction (clonazepam, nitrazepam) may also, in a somewhat similar vein, be unlikely to be affected by fluvoxamine. Using fluvoxamine and alprazolam together can increase alprazolam plasma concentrations. If alprazolam is coadministered with fluvoxamine, the initial alprazolam dose should be reduced to the lowest effective dose. As with all SSRI medications, using fluvoxamine with NSAIDs like ibuprofen may increase the risk of bleeding, particularly in the GI tract. Fluvoxamine is contraindicated with other medications that increase serotonin (dextromethorphan, ondansetron, amphetamine, sumatriptan, Tramadol, Hypericum perforatum, etc.). Combining these medications may rarely lead to a life-threatening complication known as serotonin syndrome. Fluvoxamine and ramelteon coadministration is not indicated. Fluvoxamine has been observed to increase serum concentrations of mirtazapine, which is mainly metabolized by CYP1A2, CYP2D6, and CYP3A4, by three- to four-fold in humans. Caution and adjustment of dosage as necessary are warranted when combining fluvoxamine and mirtazapine. Fluvoxamine seriously affects the pharmacokinetics of tizanidine and increases the intensity and duration of its effects.
Paclitaxel is one of several cytoskeletal drugs that target tubulin. Paclitaxel-treated cells have defects in mitotic spindle assembly, chromosome segregation, and cell division. Unlike other tubulin-targeting drugs, such as colchicine, that inhibit microtubule assembly, paclitaxel stabilizes the microtubule polymer and protects it from disassembly. Chromosomes are thus unable to achieve a metaphase spindle configuration. This blocks the progression of mitosis and prolonged activation of the mitotic checkpoint triggers apoptosis or reversion to the G0-phase of the cell cycle without cell division. The ability of paclitaxel to inhibit spindle function is generally attributed to its suppression of microtubule dynamics, but other studies have demonstrated that suppression of dynamics occurs at concentrations lower than those needed to block mitosis. At the higher therapeutic concentrations, paclitaxel appears to suppress microtubule detachment from centrosomes, a process normally activated during mitosis. Paclitaxel binds to the beta-tubulin subunits of microtubules.
=== Music === The majority of Library of Ruina's soundtracks were created by two music studios, South Korean game sound studio Studio EIM and Japanese indie band Mili. Studio EIM composed music for the main menu, receptions, Abnormality suppressions, and floor realizations. In a typical reception, the floor's background music changes corresponding to its emotion level. For Library of Ruina, Mili made a mini album, To Kill A Living Book, with seven out of the eight songs being tailored to specific characters. A small number of other tracks were borrowed from the prequel installment, Lobotomy Corporation.
Sources: en.wikipedia.org
Lyophilized products should be stored in airtight containers, protected from moisture and light, at the temperature specified by the manufacturer. Many require refrigeration at 2–8 °C, while some need frozen storage. Always check the product label for specific conditions.
Moisture can cause the porous cake to collapse, increase molecular mobility, and accelerate chemical degradation. It may also promote microbial growth if the product lacks preservatives. Proper sealing and handling are essential to maintain stability.
Some formulations contain labile biological molecules that degrade even in the dry state at higher temperatures. Others have a low glass transition temperature, meaning the cake can soften or collapse at room temperature. Cold storage reduces molecular motion and slows degradation.
Conventional drying uses heat to evaporate liquid water, often at temperatures that can degrade sensitive materials. Lyophilization freezes the material first and then removes water by sublimation under vacuum. This avoids prolonged exposure to liquid water and high heat.