If you have been reading about glass transition and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2025-10-18. Where a claim depends on a specific study, the study is described rather than over-claimed.
Handling practices aim to prevent moisture ingress and mechanical damage. Vials should remain stoppered and crimped until use, and reconstitution should follow the labeled diluent and volume. Shipping may involve temperature-controlled containers and desiccants, but direct contact between desiccant and product is avoided. Regulatory guidance expects documented storage conditions, excursion assessments, and stability commitments. Open questions remain about how best to predict long-term stability from short accelerated studies for every formulation class.
After lyophilization, the product is usually a porous cake or powder with a large internal surface area. This structure can absorb moisture quickly if exposed to humid air, so vials are sealed under vacuum or an inert gas. Moisture uptake may lower the glass transition temperature of the dried matrix and accelerate chemical or physical degradation. Storage conditions therefore depend on the formulation, container, and intended shelf life. Some products remain stable at room temperature, while others require refrigeration or freezing.
Quality control for lyophilized products includes appearance, cake structure, reconstitution time, pH, residual moisture, and potency. Residual moisture is a key attribute because excess water can reduce stability, while excessively low moisture may cause structural changes or aggregation in some systems. Stability studies compare real-time and accelerated conditions to estimate shelf life. Analytical methods must be validated for the specific matrix, container, and moisture range. Sterility and container integrity are also monitored for sterile products.
Stability studies examine how temperature, humidity, and time influence a lyophilized product. Accelerated conditions provide early information about degradation pathways, while long-term studies support shelf-life claims. The glass transition temperature of the dried formulation can indicate its physical stability, and storage above this temperature may increase molecular mobility and lead to collapse or aggregation. Container closure integrity also matters because moisture or oxygen ingress can degrade the product, so vial stoppers and seals are part of the quality system.
Handling and storage practices aim to keep the cake intact and dry. Vials are typically stored upright at controlled temperatures, often between 2 °C and 8 °C or at -20 °C for longer-term use. Reconstitution involves adding a suitable diluent and gently mixing until the solid dissolves. Shaking or rapid injection of diluent can create foam or damage sensitive molecules. Once reconstituted, the product may require refrigeration and use within a defined period.
| Property | Value | Notes |
|---|---|---|
| Typical appearance | White to off-white porous cake or powder | Color and structure vary with formulation. |
| Typical reconstitution time | Seconds to several minutes | Diluent, agitation, and temperature affect rate. |
| Typical storage temperature | 2–8 °C, 15–25 °C, or ≤−20 °C | Product-specific; protect from moisture and light. |
| Typical container closure | Glass vial with rubber stopper and crimp seal | Closure must limit moisture ingress. |
| Typical stability indicator | Residual moisture, potency, and reconstitution time | Monitored throughout shelf life. |
Lyophilized products are typically hygroscopic and require protection from moisture during storage. Manufacturers seal them in glass vials, often under vacuum or an inert gas such as nitrogen. The container closure system, including the stopper and crimp seal, must prevent water vapor ingress. Storage temperature varies from controlled room temperature to refrigerated or frozen conditions, depending on the formulation. Humidity-controlled environments are essential because even brief exposure to ambient air can degrade the product.
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.
Lyophilized products are typically stored as sealed solids in vials or syringes. Moisture ingress is a major concern because many dried cakes are hygroscopic and can lose stability when exposed to humid air. Storage temperature depends on the formulation; some products are kept refrigerated, while others are stable at room temperature. Container closure integrity and headspace moisture are often monitored. Light protection may also be required for some photosensitive materials.
Quality control for lyophilized materials includes visual inspection, residual moisture measurement, and reconstitution testing. Cake appearance can reveal process problems such as collapse, shrinkage, or meltback, although appearance alone does not prove potency. Residual moisture is commonly measured by Karl Fischer titration or by loss on drying. Reconstitution time is checked because a slow or incomplete dissolve can indicate a change in pore structure. Stability studies track these attributes over time under defined temperature and humidity conditions.
Analytical methods for lyophilized solids must account for the low moisture content and the fragile cake. Karl Fischer titration is widely used for water content, while near-infrared spectroscopy can measure moisture non-destructively in sealed containers. X-ray diffraction and modulated differential scanning calorimetry help identify crystalline or amorphous phases. Residual solvent analysis may be needed if organic solvents were used during formulation. The combination of these methods supports batch release and long-term stability assessment.
Solute carrier family 25 member 39 is a protein that in humans is encoded by the SLC25A39 gene. The protein has been shown to be necessary for the import of the major antioxidant glutathione into the mitochondria.
=== Personal struggles === Kidder received a diagnosis of bipolar disorder in 1988, which she rejected at the time, and refused the recommended lithium treatment. In 1990, while filming the pilot of a proposed television series Nancy Drew and Daughter, Kidder was in a car crash that injured her spine and left her partially paralyzed. She was unable to work for two years, resulting in debts over $800,000. Kidder attempted to sue the Canadian producer, Nelvana, for $1 million in damages, but did not receive a settlement, and launching the suit rendered her ineligible for Canadian workers' compensation. While convalescing, Kidder said she finally "was able to accept the diagnosis" (of bipolar disorder). She later spoke openly about treatment of her bipolar disorder via alternative medicine. In 1996, she experienced a manic episode in Los Angeles. At the time, Kidder had been working on an autobiography when her laptop computer became infected with a virus, which caused it to crash and her to lose three years' worth of drafts. Kidder flew to California to have the computer examined by a data-retrieval company that was unable to retrieve the lost files. This prompted her to enter a manic state and she disappeared for four days. She was later found by a homeowner in the backyard of a Glendale residence, and was taken by the Los Angeles Police Department to Olive View–UCLA Medical Center in a distressed state, the caps on her teeth having been knocked out during a rape attempt. She was subsequently placed in psychiatric care.
==== Economy ==== According to Tel Aviv University economist Tomer Fadlon, there would be long-term and significant effects on northern Israel's economy if its population did not return. He further said that even if Israel achieved victory in Gaza, the north would possibly not see an economic recovery. The conflict severely hurt the tourism industry in the north, which employs many people. Many factories in the region have not shut down but suffered labor shortages of up to 50%. According to an estimate by the Bank of Israel in November 2023, the Israeli economy suffers the loss of 590 million shekels ($158 million) every week due absence of work caused by the evacuation of 144,000 people after the Gaza war, 40% of them from the north. Once-robust communities such as Snir and Kiryat Shmona were mostly emptied following the evacuation orders in northern Israel. Kiryat Shmona was planned to be used by food technology businesses, but companies left following the city's evacuation in October 2023. Northern Israel has one-third of Israel's agricultural land, and the occupied Golan Heights and Galilee accounted for 73% of Israel's annual egg production; however, after the outbreak of the conflict, few people remained in the north to tend chicken coops, resulting in a decline in domestic egg production. In August 2024, the Ministry of Agriculture and Food Security approved a quota for the import of 45 million eggs due to the anticipated drop in local production over the conflict and other reasons.
==== Ion exchange ==== It is common for medium active wastes in the nuclear industry to be treated with ion exchange or other means to concentrate the radioactivity into a small volume. The much less radioactive bulk (after treatment) is often then discharged. For instance, it is possible to use a ferric hydroxide floc to remove radioactive metals from aqueous mixtures. After the radioisotopes are absorbed onto the ferric hydroxide, the resulting sludge can be placed in a metal drum before being mixed with cement to form solid waste. In order to get better long-term performance (mechanical stability) from such forms, they may be made from a mixture of fly ash, or blast furnace slag, and portland cement, instead of normal concrete (made with portland cement, gravel and sand).
Sources: en.wikipedia.org
"Assassination on City Hall": dominated by Germans, the Execution Department of Worker's and Soldier's Council proceeded to Poznań's City Hall, an armed group of Poles forces it to change four of the German delegates with Polish ones: Bohdan Hulewicz, Mieczysław Paluch, Henryk Śniegocki and Zygmunt Wiza. Poles thus gain control over the headquarters of Poznań Garrison and 5th Corps. 17 November 1918: the Commission of the NRL calls for a one-time collection of money called a "national tax". 18 November 1918: elections to Poviat's People's Councils and members of the partition's Sejm (1399 MPs). 20 November 1918: the Polish government in Warsaw publishes przyłączenie Wielkopolski będzie jednym z pierwszych naszych zadań (the joining of Greater Poland will be one of our first tasks). 3 December 1918: The Partition Sejm of Poznań begins its official proceedings in the "Apollo" Cinema. MPs represent all lands of the Prussian Partition and Polish economic emigration, mainly from Westfalen. 5 December 1918: the end of the Partition Sejm, which declared its desire for unification with the other partitions in a renewed Poland, and the NRL officially elected its members. 6 December 1918: the first meeting of the NRL has Bolesław Krysiewicz become the speaker. Election of executive body, Commission of the NRL, formed by representatives of Greater Poland - Stanisław Adamski and Władysław Seyda; Upper Silesia: Wojciech Korfanty and Józef Rymer; Eastern Pomerania: Stefan Łaszewski; Kuyavia: Adam Poszwiński.
This remains a challenge in clinical practice due to a lack of reliable markers. Many other conditions lead to similar clinical as well as pathological pictures. To diagnose hepatotoxicity, a causal relationship between the use of the toxin or drug and subsequent liver damage has to be established, but might be difficult, especially when idiosyncratic reaction is suspected. Simultaneous use of multiple drugs may add to the complexity. As in acetaminophen toxicity, well established, dose-dependent, pharmacological hepatotoxicity is easier to spot. Several clinical scales such as CIOMS/RUCAM scale and Maria and Victorino criteria have been proposed to establish causal relationship between offending drug and liver damage. CIOMS/RUCAM scale involves a scoring system that categorizes the suspicion into "definite or highly probable" (score > 8), "probable" (score 6–8), "possible" (score 3–5), "unlikely" (score 1–2) and "excluded" (score ≤ 0). In clinical practice, physicians put more emphasis on the presence or absence of similarity between the biochemical profile of the patient and known biochemical profile of the suspected toxicity (e.g., cholestatic damage in amoxycillin-clavulanic acid).
The draw started with Pot 1 and ended with Pot 4, with each team selected and then allocated into the first available group alphabetically. For the purpose of the match schedule, the Pot 1 teams were automatically drawn into position 1 of each group. For the remaining pots, FIFA established a predetermined pattern to define the position of teams based on their pot and the group they were drawn into.
Sources: en.wikipedia.org
Collapse occurs when the product temperature rises above its collapse or eutectic temperature during drying. The frozen matrix loses structure, producing a shrunken or melted appearance. This can slow reconstitution and may affect stability.
Karl Fischer titration is a common method, along with loss on drying and thermogravimetric analysis. Each method has different sensitivity and sample requirements. Results should be interpreted with the product's formulation and container in mind.
No. Lyophilization removes water but is not a sterilization step. Sterile products are typically filtered and filled aseptically before freezing, and container closure integrity is maintained afterward.
Residual moisture can influence chemical degradation, cake collapse, and long-term stability. Low moisture levels usually improve stability, but each product has an optimal range.